Condo Conversion Underwriting: Sellout Schedule, Absorption Rate, and the Convert-vs-Hold Decision

Key Takeaways

What a Condo Conversion Is

A condo conversion is the legal and physical transformation of an existing rental property (most commonly a multifamily apartment building, but sometimes an office, hotel, or warehouse) into individually owned condominium units offered for sale. The process involves filing a condominium declaration with the local recording office, establishing a homeowners association (HOA), renovating units to for-sale standards, and selling individual units to buyers over a sellout period.

The economic premise is simple: in many markets, the aggregate value of individual condo units exceeds the value of the same building as a stabilized rental property. A 100-unit apartment building generating $2.4 million of net operating income and valued at $40 million as a rental (6.0% cap rate) may be worth $35 million to $42 million as individually sold condos at $350,000 to $420,000 per unit. The spread between the rental valuation and the condo sellout value, after accounting for conversion costs, selling expenses, and the time value of money, is the conversion profit.

Not every rental building is a conversion candidate. The economics work when three conditions align: (1) per-unit condo prices in the submarket meaningfully exceed the per-unit rental value (typically by 30% or more), (2) the building's physical condition supports renovation to for-sale standards at a reasonable cost per unit, and (3) the legal and regulatory environment permits conversion (some jurisdictions restrict or prohibit conversions of rent-stabilized buildings, require tenant purchase rights, or impose lengthy notification periods).

The underwriting framework for a condo conversion differs fundamentally from a hold-and-operate rental analysis. A rental analysis uses stabilized NOI, a capitalization rate, and a terminal value at disposition. A conversion analysis uses a sellout schedule: the month-by-month projection of unit closings, gross sale proceeds, selling costs, and net cash flow, discounted back to a present value. The sellout schedule replaces the terminal cap rate as the primary valuation mechanism.

Gross Sellout Value

Gross sellout value (GSV) is the total revenue from selling all condominium units at their asking prices before any deductions. It is the top-line number in the conversion pro forma and the starting point for the entire analysis.

Calculating GSV requires pricing every unit individually, then summing the prices. A 100-unit building with a uniform $350,000 price has a $35 million GSV. In practice, units are rarely priced uniformly. Floor premiums, view premiums, unit size differences, renovated vs. original condition, and parking assignments all create pricing dispersion. A well-underwritten GSV reflects this dispersion rather than averaging it away.

The inputs to GSV are comparable condo sale prices in the immediate submarket, adjusted for condition, size, floor, view, and amenity package. The appraiser's term for this is "anticipated gross revenue" or "prospective gross sellout," and the methodology follows the subdivision analysis approach prescribed by USPAP for proposed or converting condominium projects.

Three adjustments convert GSV to net sellout value (NSV):

1. Brokerage commissions. Typically 4% to 6% of gross sale price. The developer usually hires a project sales team (2% to 3% of gross) and offers a co-broke commission to buyer agents (2% to 3%). In markets where buyer agency compensation has shifted post-NAR settlement, the developer may offer a smaller co-broke or none, but most conversion developers continue to offer 2% to 2.5% to maintain traffic.
2. Closing costs and credits. Transfer taxes, title insurance (if paid by seller), recording fees, and buyer closing cost credits typically total 1% to 2% of gross. Transfer tax rates vary by state and municipality (New York City charges 1% to 1.425% on the seller; Florida charges $0.70 per $100; Illinois charges $0.50 per $500 at the state level plus local surcharges). Developers frequently offer closing cost credits of $5,000 to $15,000 per unit as an absorption incentive, particularly in the early and late stages of sellout.
3. Marketing and sales center costs. The sales center buildout, marketing collateral, digital advertising, and staging costs are typically 1% to 2% of gross for a conversion (lower than ground-up condo development, where sales centers can run 2% to 4%). These costs are partially fixed (the sales center exists regardless of how fast units sell) and partially variable (advertising spend scales with inventory duration).

A conservative underwriting convention: deduct 8% from GSV to arrive at NSV. This accounts for 5% total commissions, 1.5% closing costs and transfer taxes, and 1.5% marketing. The actual deduction should be built up from local comparables and specific deal terms, but 8% is the sanity-check range for suburban conversions in moderate-cost markets. Urban luxury conversions may require 9% to 11% due to higher transfer taxes and marketing spend.

Unit Pricing Strategy

Unit pricing in a condo conversion follows the same principles as any for-sale residential development, but the conversion context adds constraints. The units already exist. Their sizes are fixed. Their layouts are fixed. The developer cannot redesign a floor plate to maximize pricing. The pricing strategy must work with the existing unit mix.

The standard pricing framework uses four tiers of adjustment to a base price per square foot:

1. Base price per square foot. Established from comparable condo sales in the submarket, adjusted for condition and amenity package. If comparable one-bedroom condos in the area trade at $375 to $425 per square foot in renovated condition, the base for a conversion project delivering renovated units should fall within that range. If the conversion delivers units in original condition with an improvement allowance, the base drops by the anticipated per-square-foot renovation cost ($50 to $100 per square foot for a moderate renovation).
2. Floor premium. Higher floors command a premium, typically 1% to 3% per floor for mid-rise buildings and 0.5% to 1.5% per floor for low-rise garden-style buildings. A 4-story garden-style walkup might apply 0% for the first floor, 1.5% for the second, 3% for the third, and 4.5% for the fourth. A 12-story mid-rise might apply 0% for floors 2 to 4, 2% for floors 5 to 7, 5% for floors 8 to 10, and 8% to 10% for floors 11 to 12.
3. View premium. Units with unobstructed views (water, park, skyline, mountain) command premiums of 5% to 20% over comparable units without views. Interior-facing units or units facing parking lots may receive a 3% to 8% discount to the base. The view premium interacts with the floor premium: a high-floor unit with a view captures both adjustments.
4. Unit type and layout adjustments. Corner units with additional windows typically receive a 3% to 5% premium. Units with balconies or patios may command 2% to 7% premiums depending on the market. Units adjacent to elevators, trash rooms, or mechanical equipment receive discounts of 2% to 5%. End units in garden-style buildings with additional side windows command premiums similar to corner units.

The aggregate pricing schedule must be internally consistent. If a building has 30 one-bedroom units, 50 two-bedroom units, and 20 three-bedroom units, the two-bedroom price should exceed the one-bedroom by roughly the additional square footage times the base price per square foot, plus any bedroom count premium. Markets vary on whether additional bedrooms carry a premium beyond the raw square footage. Suburban family markets typically price additional bedrooms at a 2% to 5% premium above the square footage value. Urban markets with smaller household sizes show less bedroom premium.

A practical approach: build the pricing schedule in a matrix with unit type on one axis and floor/exposure on the other. Fill in the base prices first, then layer adjustments. Sum the column to confirm the GSV. Walk the schedule against the five or six most recent comparable sales and adjust if any unit type is priced more than 10% above or below the comp-adjusted range. If you cannot find support for a price, the price is wrong.

Absorption Rate Estimation

Absorption rate is the pace at which units sell. In condo conversion underwriting, it is measured in units per month (or closings per month, which is different from contracts per month because of the contract-to-closing lag). The absorption rate is the single most sensitive variable in the conversion pro forma. It determines the length of the sellout period, which determines the carrying costs, which determines the net present value.

As Thesis Driven's absorption rate guide explains, absorption in for-sale residential is driven by three forces: market demand (how many qualified buyers exist in the submarket at the offered price point), competitive supply (how many comparable units are available from competing projects), and project-specific factors (location, product quality, developer reputation, sales and marketing execution).

Estimating absorption for a conversion project starts with the submarket data. Pull the trailing 12-month condo sale volume from the local MLS or data provider (CoStar, Redfin, or local MLS feeds). Calculate the monthly absorption rate for the submarket: total closed sales divided by 12, divided by the average standing inventory. This gives you the submarket absorption coefficient. Then estimate your project's capture rate: what share of total submarket demand will your project capture?

A realistic capture rate for a single conversion project in a diversified submarket is 5% to 15% of total monthly demand. If the submarket absorbs 40 condo units per month across all projects and your project captures 10%, your expected absorption is 4 units per month. If the submarket absorbs 80 units per month and you capture 8%, your expected absorption is roughly 6 units per month.

Absorption Benchmarks by Project Type

Two factors that institutional underwriters frequently miss. First, absorption is not linear. Most conversion projects follow an S-curve: slow initial sales during the presale period (buyers are cautious before the project is real), accelerating absorption during the middle third of sellout (social proof builds, the project is visibly progressing), and deceleration in the final third (the remaining units are the hardest to sell because they are the least desirable or the most expensive). Second, absorption interacts with pricing. If sales stall, the developer faces a choice between holding price and extending the timeline or cutting price and accelerating absorption. The pro forma should model the expected absorption curve, not a flat monthly rate.

Sellout Schedule Construction

The sellout schedule is the month-by-month projection of unit closings, gross sale proceeds, selling costs, and net cash flow from the conversion. It is the core deliverable of the conversion underwriting process. Every other number in the pro forma flows from the sellout schedule or feeds into it.

A sellout schedule has six columns for each month:

1. Units closed. The number of units that close (transfer title) in that month. This is driven by the absorption rate estimate, shaped by the S-curve, and constrained by presale requirements and construction completion.
2. Cumulative units closed. Running total of units closed to date. When this equals the total unit count, the project is sold out.
3. Gross sale proceeds. The sum of closing prices for all units closing in that month. This is not a flat average times units; it should reflect the specific units projected to close (lower-priced units tend to sell first, higher-priced units later, though this varies by project).
4. Selling costs. Commissions, transfer taxes, closing cost credits, and per-closing transaction costs for that month's closings. Typically 6% to 9% of gross sale proceeds.
5. Net sale proceeds. Gross minus selling costs. This is the cash received by the developer from that month's closings.
6. Cumulative net sale proceeds. Running total of net cash received from all closings to date.

Three additional rows run alongside the sellout schedule:

• Operating expenses on unsold units. The developer pays HOA fees, taxes, insurance, and maintenance on unsold units. These costs decline as units close and transfer to individual buyers. Monthly carrying cost per unsold unit typically runs $400 to $800 depending on the market and building type.
• Interest carry on conversion financing. The construction or conversion loan accrues interest on the outstanding balance. As units sell and loan principal is paid down, the interest carry declines. Monthly interest cost depends on the outstanding balance and the loan rate (typically prime + 2% to 4% for conversion financing, or approximately 10% to 12% in 2026).
• Net monthly cash flow. Net sale proceeds minus operating carry minus interest carry. This line may be negative in the early months (before meaningful closings begin) and grows increasingly positive as absorption accelerates.

Discount Rate Selection

The discount rate applied to the sellout cash flow stream converts the future net sale proceeds into a present value. This is the second most sensitive variable in the pro forma after absorption (and in some deals, the most sensitive). A 100-basis-point change in the discount rate on an 18-month, $32 million net sellout changes the NPV by approximately $250,000 to $350,000. A 500-basis-point change can move it by $1.5 million or more.

The discount rate for a condo sellout is not the same as the discount rate for a rental hold DCF. A rental hold DCF typically uses a property-level discount rate of 7% to 10%, anchored by cap rate surveys and transaction data. A condo sellout DCF uses a higher rate because the cash flows are inherently riskier: they depend on individual buyer decisions, mortgage availability, local market sentiment, and the developer's sales execution. The sellout is a liquidation, not an income stream.

Discount Rate Ranges by Risk Profile

Five factors drive the discount rate selection for a specific project:

1. Presale percentage. The single largest risk reducer. A project that has contracted 60% of its units before construction begins has substantially less sellout risk than a project with no presales. Each 10% increment of presales above the lender minimum typically justifies a 50 to 100 bps reduction in the discount rate.
2. Market conditions. Rising for-sale prices and tightening inventory support lower discount rates. Falling prices, rising rates, and growing inventory demand higher rates. The directionality of the market matters as much as the current level.
3. Developer track record. A developer with three or more completed conversions in the same submarket has demonstrated the ability to execute. Lenders and appraisers will accept a lower discount rate for proven operators. A first-time converter faces a 200 to 400 bps premium.
4. Financing structure. A fully funded conversion with committed takeout financing carries less execution risk than a project reliant on speculative construction financing with no takeout. The financing structure can shift the discount rate by 100 to 200 bps.
5. Buyer financing availability. This is where the 2026 Fannie Mae changes matter. If the project meets Fannie Mae eligibility requirements (including the new 15% reserve minimum and insurance deductible caps), buyers can obtain conventional 30-year fixed-rate mortgages. If the project fails to meet these requirements, buyers are limited to portfolio loans, jumbo financing, or non-QM products, which reduces the buyer pool and slows absorption. A project that is not Fannie-eligible may require a 200 to 300 bps premium to the discount rate.

Presale Requirements

Presale requirements are the lender-imposed minimums for the number or dollar value of units that must be under contract before the conversion loan funds (or before the next funding draw is released). They serve two purposes: they reduce the lender's sellout risk by demonstrating market demand, and they generate cash deposits that provide a cushion against buyer default.

Typical presale thresholds for conversion financing:

• Conventional construction/conversion lenders. 50% to 70% of total units under contract with hard deposits, or 50% to 70% of gross sellout value contracted. The higher end of the range applies to first-time developers, secondary markets, and projects with higher per-unit prices.
• Agency lenders (Fannie Mae / Freddie Mac). For projects seeking end-buyer Fannie Mae eligibility, the Fannie Mae Selling Guide requires that the project meet specific presale and owner-occupancy thresholds before individual unit loans are eligible for purchase. The general requirement is that at least 50% of units be sold (or under contract to bona fide purchasers) and that no single entity own more than a specified percentage of total units. The 2026 updates impose additional requirements around reserve funding and insurance coverage. As InterCap Lending's analysis of the 2026 changes details, the practical effect is that projects below 50% sold must rely on portfolio or non-QM financing for individual unit buyers, which constrains the buyer pool.
• Hard money / bridge lenders. 0% to 30% presale requirements. These lenders accept higher sellout risk in exchange for higher interest rates (12% to 16%) and origination fees (2% to 4 points). Hard money is used for acquisitions where the developer needs to close before a presale campaign can be conducted, with the intent to refinance into conventional conversion financing once presales are achieved.

Hard Deposit Structures

A presale contract is only as strong as the deposit backing it. Lenders distinguish between soft deposits (refundable under various contingencies) and hard deposits (non-refundable after a specified due diligence period). Only hard deposits count toward presale thresholds for most institutional lenders.

Typical deposit structures in condo conversions:

• Initial deposit at contract signing. 5% to 10% of purchase price. Held in escrow. Refundable during a 7 to 15-day inspection period (varies by state), then goes "hard" (non-refundable).
• Second deposit at construction milestone. An additional 5% to 10% due when renovation reaches a specified completion milestone (often 50% or at certificate of occupancy). Goes hard upon payment.
• Total hard deposits at closing. 10% to 20% of purchase price, already paid and non-refundable, applied to the buyer's down payment at closing.

The contract-to-closing timeline for presale units is typically 6 to 18 months, depending on the scope of renovation. During this period, the developer carries the risk that buyers may default on their contracts and forfeit their deposits. The developer keeps the deposits (subject to state law and the specific contract terms) and must resell the unit. In a rising market, the forfeited deposit plus a resale at a higher price makes the developer whole or better. In a declining market, the forfeited deposit may not cover the price decline plus the cost of carrying and reselling the unit.

Conversion Costs and Capital Stack

Conversion costs are the capital required to transform a rental building into a condominium project. They fall into three categories: hard costs (physical renovation), soft costs (legal, design, permitting, marketing), and carrying costs (interest, taxes, insurance, and operating expenses during the renovation and sellout period).

Hard Costs

Hard costs for a condo conversion depend on the scope of renovation. Three tiers are common:

Common area improvements are required regardless of unit renovation scope. The lobby, hallways, elevator cabs, landscaping, parking areas, and any shared amenity spaces must be brought to for-sale standards. Common area costs typically add $3,000 to $8,000 per unit for cosmetic improvements and $8,000 to $20,000 per unit for substantial upgrades.

Soft Costs

Soft costs for a condo conversion include:

• Legal and condo declaration. $50,000 to $150,000 for the condominium offering plan or declaration, HOA formation documents, purchase contracts, and regulatory filings. In states that require attorney general approval (New York, Florida, Massachusetts), the legal costs are at the higher end and the timeline extends by 3 to 6 months.
• Architecture and engineering. $25,000 to $75,000 for renovation plans, unit surveys, as-built drawings, and engineering assessments (structural, mechanical, electrical).
• Permitting and approvals. $10,000 to $50,000 depending on jurisdiction. Some municipalities require a special permit or zoning variance for conversion. Others treat it as a by-right change in use.
• Reserve study. $5,000 to $15,000 for a professional reserve study, which is now effectively required to meet the Fannie Mae 15% minimum reserve standard. The reserve study identifies all building components, estimates their remaining useful life, and calculates the annual contribution required to fund replacements without special assessments.
• Marketing and sales. $100,000 to $300,000 for sales center buildout, brochures, website, photography, staging, and digital advertising. This is a front-loaded cost: most of it is spent before the first unit closes.

Capital Stack

The capital stack for a condo conversion is structured differently from a rental acquisition. The primary difference is the exit: the rental acquisition exits through refinance or sale of the entire building, while the conversion exits through individual unit sales over a sellout period. This changes the financing structure.

A typical conversion capital stack:

• Senior conversion/construction loan. 60% to 75% of total project cost (acquisition + renovation). Interest-only, floating rate (prime + 2% to 4%), 18 to 36 month term with extensions. The lender requires a minimum presale threshold (50% to 70%) before funding renovation draws. As units sell, the loan balance is paid down through a release price mechanism (typically 105% to 115% of the allocated loan amount per unit). Evoque Commercial's condo financing overview provides a useful summary of current lender terms.
• Developer equity. 25% to 40% of total project cost. Funded at closing, with a portion held in reserve for cost overruns and carry during the presale period.
• Presale deposits. Not part of the capital stack directly, but presale deposits (10% to 20% of contracted unit prices) are held in escrow and applied at closing, reducing the buyer's mortgage requirement and providing the developer with evidence of demand for the lender.

HOA Budget and Reserve Study

When a building converts to condominium, the developer must establish a homeowners association (HOA) with an initial operating budget and reserve fund. The HOA budget governs the monthly fees that unit owners pay for common area maintenance, insurance, utilities, management, and reserves. Getting the budget right at the outset matters for two reasons: (1) an unrealistically low budget creates deferred maintenance problems and potential special assessments within the first few years, which depresses resale values and generates buyer litigation, and (2) an unrealistically high budget slows absorption because buyers qualify based on total housing payment (mortgage + HOA fees + taxes + insurance), and excessive HOA fees reduce their purchasing power.

Initial Budget Components

A condo HOA budget typically includes:

• Property management. $150 to $300 per unit per year for third-party management, or a percentage of the total budget (8% to 12%).
• Insurance (master policy). The building's master insurance policy covers the structure, common areas, and liability. Cost varies dramatically by location, building age, and construction type. Coastal markets (Florida, Carolinas, Gulf states) have seen insurance costs triple since 2020. A mid-rise building in a non-coastal market might pay $400 to $800 per unit per year. The same building in coastal Florida might pay $1,500 to $4,000 per unit per year.
• Utilities (common area). Hallway and lobby lighting, elevator power, common area HVAC, water/sewer for common areas, landscaping irrigation. $200 to $500 per unit per year depending on climate and building type.
• Maintenance and repairs. Routine maintenance of common areas, elevator service contracts, landscaping, pest control, snow removal (where applicable). $300 to $800 per unit per year.
• Reserves. The contribution to the reserve fund for future capital expenditures (roof replacement, elevator modernization, parking lot repaving, exterior painting). This is the line item most affected by the 2026 Fannie Mae changes.

The 2026 Fannie Mae Reserve Requirement

Effective August 3, 2026, Fannie Mae requires that condominium projects allocate a minimum of 15% of the annual operating budget to reserves (up from the previous 10% guideline). This applies to all projects where individual unit loans are sold to Fannie Mae, which covers the majority of conventional mortgage originations. The requirement reflects lessons from the Champlain Towers South collapse in Surfside, Florida, and the subsequent wave of state-level reserve study mandates.

For a conversion developer, the 15% minimum has a direct financial impact on absorption. Consider a building with a $500,000 annual operating budget. At 10% reserves, the reserve contribution is $50,000 per year ($500 per unit per year on a 100-unit building, or $42 per unit per month). At 15%, it is $75,000 per year ($750 per unit per year, or $63 per unit per month). The $21 per month per unit increase in HOA fees may seem small, but it reduces the buyer's qualifying income capacity by roughly $8,000 per year at standard debt-to-income ratios, which can shrink the qualified buyer pool by 3% to 7% at moderate price points.

The reserve study itself must demonstrate that the 15% allocation is sufficient to fund identified capital replacements over a 20 to 30 year horizon without special assessments. If the reserve study shows that 15% is insufficient (common for older buildings with deferred maintenance), the HOA must budget a higher percentage, and the developer must disclose this in the offering plan. Buildings with fully funded reserves and a clean reserve study sell faster and at higher prices because buyers and their lenders have confidence in the building's financial health.

Insurance Compliance

Insurance requirements for condominium projects have tightened significantly since 2021, driven by catastrophic losses (Champlain Towers South), rising reinsurance costs, and regulatory response. For a condo conversion, meeting insurance standards is not optional: it is a prerequisite for buyer financing.

Master Policy Requirements

The building's master insurance policy must provide:

• Property coverage. Replacement cost coverage for the building structure and all common elements. The coverage amount must equal or exceed 100% of the insurable replacement cost as determined by a current appraisal or insurance evaluation.
• Liability coverage. Commercial general liability of at least $1 million per occurrence, $2 million aggregate, covering the HOA, the common areas, and the building structure.
• Fidelity bond / crime coverage. Required by Fannie Mae for projects with more than 20 units. Coverage amount must equal at least 3 months of HOA assessments plus reserve balances.

The $50,000 Per-Unit Deductible Cap

Effective July 2026, Fannie Mae imposes a maximum per-unit deductible of $50,000 on the master policy. If the building's master policy has a deductible exceeding $50,000 per unit (common in coastal Florida, where hurricane deductibles can run 3% to 5% of building value), the project fails the Fannie Mae eligibility test. Buyers cannot obtain Fannie Mae-backed mortgages, and the developer must either negotiate a lower deductible (at higher premium cost), establish a deductible reserve fund within the HOA budget, or accept a smaller buyer pool limited to portfolio and non-QM financing.

The deductible cap interacts with the reserve requirement. If the master policy has a $50,000 per-unit deductible, the HOA should establish a dedicated deductible reserve sufficient to cover the maximum deductible exposure without a special assessment. For a 100-unit building with a $50,000 per-unit deductible, the maximum deductible exposure on a building-wide claim is $5 million. Building a reserve to cover 50% of that exposure ($2.5 million) would require a special assessment or a significantly elevated monthly contribution. This is why the deductible cap matters: it forces a choice between higher insurance premiums (lower deductible) and higher reserve contributions (to cover the deductible), both of which increase the monthly HOA fee and reduce buyer purchasing power.

Individual Unit Coverage (HO-6)

Each unit owner is responsible for their own HO-6 policy covering interior improvements, personal property, and personal liability. Fannie Mae requires unit buyers to maintain HO-6 coverage as a condition of the mortgage. The conversion developer should factor HO-6 costs ($300 to $800 per year in most markets) into the buyer's total housing cost calculation when sizing the unit pricing strategy.

State-by-State Legal Framework

Condo conversion is governed by state and local law, and the regulatory environment varies dramatically by jurisdiction. A conversion that is by-right in one state may require legislative approval in another. The legal framework affects the timeline, cost, and feasibility of the conversion.

Conversion Notice Requirements

Most states require the developer to provide existing tenants with advance notice of the conversion. Notice periods range from 60 to 120 days depending on the jurisdiction:

• 60-day notice states. California (outside SF and LA), Texas, most Southeast and Mountain West states. The developer must provide 60 days written notice to existing tenants before filing the conversion application or before the conversion becomes effective.
• 90-day notice states. Florida, Illinois, New Jersey. Some municipalities within these states impose longer periods (Chicago requires 120 days for buildings with 7+ units).
• 120-day or longer notice states. Massachusetts (120 days), New York (90 to 120 days depending on tenant age and tenure), Washington (120 days for low-income tenants). San Francisco requires 120 days plus a lifetime lease offer for tenants who have occupied the unit for 10+ years.

Tenant Purchase Rights

Many jurisdictions grant existing tenants a right of first refusal to purchase their unit at the offered price (or at a discount) before the unit is offered to outside buyers:

• Mandatory right of first refusal. New York (non-eviction plans), Massachusetts, New Jersey, Washington D.C. The tenant has 30 to 90 days to accept or decline the purchase offer.
• Insider pricing / discount. Some jurisdictions require the developer to offer existing tenants a discount (often 5% to 15% off the public price). This reduces GSV on insider units but often accelerates absorption because tenants who purchase do not require a sellout marketing effort.
• No purchase rights. Texas, Florida (outside specific municipal ordinances), most Southeast states. Tenants receive notice but have no right to purchase.

Rent-Stabilized Unit Restrictions

In jurisdictions with rent stabilization or rent control, converting rent-regulated units is either prohibited or subject to stringent requirements:

• New York City. Rent-stabilized units can only be decontrolled through vacancy (when the tenant voluntarily vacates) or through an eviction plan (which requires 51% of tenants to agree to purchase). Non-eviction plans allow the conversion to proceed without tenant consent, but rent-stabilized tenants retain the right to remain as renters indefinitely. The developer can only sell units as they become vacant through natural turnover, which can take years or decades.
• San Francisco. Condo conversions of buildings with 6+ units are subject to an annual lottery with a cap on the number of conversions citywide. Buildings with Ellis Act evictions within the prior 10 years are ineligible.
• Boston. Rent-controlled units were decontrolled by a 1994 ballot measure, but the city has imposed local condo conversion restrictions on buildings in certain neighborhoods, including owner-occupancy requirements and tenant notification periods of 120+ days.

The legal due diligence for a conversion should include a full review of applicable state and local conversion statutes, rent stabilization applicability (if any), tenant notification requirements, tenant purchase rights, HOA formation requirements, and any municipal conversion moratoria or quotas. Engage local counsel who specializes in condominium law before committing capital.

Convert-vs-Hold NPV Analysis

The convert-vs-hold decision is the binary question at the center of every condo conversion underwriting: is the property worth more as individually sold condominiums or as a held rental asset? The analysis compares the NPV of the conversion sellout to the NPV of continuing to operate the property as a rental.

The framework is straightforward. On one side, calculate the NPV of the conversion: net sellout proceeds over the sellout period, minus conversion costs (renovation, legal, soft costs), minus carrying costs (interest, taxes, operating expenses on unsold units), discounted at the appropriate sellout discount rate. On the other side, calculate the NPV of the rental hold: the present value of the operating cash flow stream over a 7 to 10 year hold period, plus the present value of the terminal sale at an exit cap rate, minus the initial acquisition cost, discounted at the rental property discount rate.

The two NPVs are not directly comparable without adjustment. The conversion sellout is a 12 to 36 month execution with a definitive end date. The rental hold is a 7 to 10 year hold with ongoing operating risk and a terminal sale assumption. The risk profiles are different. The capital requirements are different. The time horizons are different. Three adjustments make the comparison apples-to-apples:

1. Normalize for equity invested. The conversion requires renovation capital on top of the acquisition cost. The rental hold requires only the acquisition cost (plus ongoing capex reserves). Compare returns per dollar of equity invested, not total NPV.
2. Normalize for time. Convert the conversion NPV to an annualized IRR that is comparable to the rental hold IRR. An 18-month conversion that generates a 25% total return is not the same as a 7-year rental hold that generates a 25% total return. The annualized IRR on the conversion is roughly 17%; the annualized IRR on the rental hold is 3.3%.
3. Account for optionality. The rental hold preserves the option to convert later. The conversion is irreversible (once units are sold, they cannot easily be reassembled). The option value of waiting is real and should be quantified, typically as a premium of 100 to 300 bps added to the conversion hurdle rate.

Worked Example: 100-Unit Conversion

Consider a 100-unit garden-style multifamily property in a suburban Sun Belt market. The building was constructed in 1998, is in good structural condition, and has a mix of one-bedroom (30 units, 750 sf avg), two-bedroom (50 units, 1,050 sf avg), and three-bedroom (20 units, 1,300 sf avg) units.

Current Rental Operation

Conversion Pro Forma

Sellout Assumptions

NPV Comparison

In this example, the conversion delivers a higher annualized IRR (15.3% vs 7.8%) and a slightly higher equity multiple (1.26x vs 1.23x) over a much shorter time horizon (21 months vs 7 years). The absolute dollar profit is also higher ($4.35M vs $3.2M). The conversion wins on all three measures. However, the conversion requires $2.7M more equity, carries sellout execution risk, and eliminates the option to hold the rental stream. The annualized IRR premium of 750 bps compensates for the execution risk, but just barely. If absorption slows to 4 units per month (extending the sellout to 25 months), the conversion IRR drops to approximately 10.5%, compressing the premium to 270 bps over the rental hold.

Sensitivity matters. Run the conversion pro forma at three absorption rates (base case, slow case at 70% of base, fast case at 130% of base) and three pricing scenarios (base, 5% down, 5% up). The nine-cell matrix shows how the return profile shifts. If conversion only works at base-case or better, the risk-adjusted decision may favor the rental hold, particularly for risk-averse institutional capital.

Five Mistakes Practitioners Make

1. Using a flat absorption rate instead of an S-curve. A flat assumption of 6 units per month for 17 months looks clean but overstates early cash flow and understates carrying costs. The S-curve (slow start, peak middle, slow finish) more accurately reflects how condo projects actually sell. The NPV difference between flat and S-curve absorption on a 100-unit, 18-month sellout is typically 3% to 5%, which can mean $500,000 or more on a $35 million gross sellout.

2. Ignoring the Fannie Mae eligibility test. A condo project that does not meet Fannie Mae requirements (reserve minimums, insurance deductible caps, owner-occupancy ratios, litigation status) loses access to the largest pool of mortgage capital. Buyers are limited to portfolio and non-QM loans with higher rates and stricter qualifying standards. The practical effect is a 15% to 25% reduction in the qualified buyer pool, which slows absorption by 1 to 3 units per month and extends the sellout by 3 to 8 months. Underwrite the Fannie Mae eligibility test as a hard constraint, not a nice-to-have.

3. Underestimating carrying costs during the tail. The last 10% to 20% of units in a conversion are the hardest to sell. They are the least desirable units (ground floor, interior facing, adjacent to mechanical rooms) or the most expensive (penthouses in a price-sensitive market). Carrying costs on unsold units do not decline linearly. The per-unit carrying cost actually increases as the denominator shrinks because fixed costs (management, insurance, common area maintenance) are spread over fewer unsold units. Model the tail explicitly.

4. Applying a rental cap rate to condo sellout proceeds. The condo sellout NPV should be calculated using a sellout-specific discount rate (5% to 15%), not the rental property cap rate (5% to 7%). The two rates serve different purposes and reflect different risk profiles. Using the rental cap rate to value the sellout overstates the conversion NPV by 15% to 30%, making bad conversions look good on paper.

5. Forgetting the conversion is irreversible. Once the condominium declaration is recorded and units are sold, the building cannot easily be reconverted to a rental. Reassembling a 100-unit condo building by purchasing all individual units is theoretically possible but practically prohibitive. The conversion decision eliminates the option to hold the rental stream. That optionality has value, and the conversion pro forma should price it by requiring a 200 to 400 bps IRR premium over the rental hold before the conversion is approved.

Model It in Apers

Related Articles

• DCF vs Direct Capitalization: When to Use Each. The valuation framework underlying the sellout DCF. How the two approaches compare and when the sellout schedule DCF is the appropriate tool.
• Multifamily Underwriting Fundamentals. The rental hold side of the convert-vs-hold analysis. How to underwrite the stabilized rental property that is the conversion candidate.
• Value-Add Multifamily: Renovation Premium Modeling. The renovation economics that apply to the physical conversion. How to size renovation budgets and model the premium achieved through unit upgrades.
• Hold Period Analysis: IRR vs Equity Multiple. The return metrics used in the convert-vs-hold decision. How to compare the short-duration conversion IRR against the longer-duration rental hold return.
• Multifamily Development, Construction, and Lease-Up. The ground-up development process that parallels the conversion renovation. How construction timelines, cost structures, and lease-up absorption compare to conversion sellout.