The Cost of a Wrong Model
Underwriting infrastructure is what turns a broker teaser into an IC memo, a term sheet into a pro forma, a stabilized asset into a projected return. Get it right and the deal earns the diligence. Get it wrong and a fifty-basis-point exit-cap assumption, mispriced by an off-by-one formula error, is a $2M valuation miss on a $40M asset. The math of underwriting matters because the numbers it produces are what capital allocates against.
Yet most shops run on models nobody documented, sheets nobody audited, formulas passed team to team via chat and email attachments. A junior analyst inherits a value-add pro forma from someone who left three years ago and ships it downstream without ever knowing why the debt tab computes DSCR the way it does. This is the baseline state of the industry, and it produces the errors it deserves.
Why the Industry Doesn't Share
Every serious shop treats its models as intellectual property. Not out of paranoia, but out of a reasonable instinct that the model is the analyst's competitive edge. The team that underwrites faster, sharper, more honestly than its competitors wins the deal. Sharing the model feels like giving up the edge.
The result is that every shop rebuilds the same base infrastructure. Every acquisition team has its own quick screener. Every value-add group has its own five-year pro forma. Every waterfall model is somebody's Frankenstein of nested IF statements from four analysts ago. The industry as a whole spends thousands of analyst-hours per year re-implementing the exact same math with the exact same corner-case errors, because sharing the base felt like giving up the edge.
The Open Model Collection
The base is not the edge. The judgment call on the tenant, the read on the neighborhood, the negotiation with the seller. Those are the edge. A well-built value-add pro forma is not where deals are won or lost. Deals are won and lost on what the sponsor does with the pro forma's output.
So we made the base open. The Apers Open Model Collection is the set of underwriting models we built for our own platform, published as spreadsheets any shop can download, use, fork, and improve. Free to use. Free to fork. Free to argue with. Free to send back with corrections.
The point is not to give everyone the same model. It is to give everyone a legible starting point. Use ours as-is if it fits. Fork it and layer in your desk's specific mechanics. Read the engineering essays to understand why we made the design choices we made, then override them for your deal. Use them as reference material for your team's onboarding. Or read them once, go build a better one, and send us that.
/ APERS