MODEL DESIGN
How to Build a LIHTC Screening Model for 4% and 9% Deals
Overview
ARTICLE IN PROGRESS
We're writing a deep engineering essay on TX-101. How we built it, the design choices behind it, and how to use it. The model itself is live and available today.
TX-101 is the affordable housing development screener for 4% and 9% LIHTC deals. The financing structures differ (tax-exempt bonds for 4%, competitive allocation for 9%) but the underlying mechanics (AMI-capped rents, per-credit equity pricing, regulatory compliance horizon) are shared. One model handles both.
Planned Sections
When the full piece is published, it will cover:
- LIHTC mechanics in one model: why 4% and 9% deals share more than they differ.
- Design choice: separating tax-exempt bond financing for 4% from competitive allocation for 9%.
- Design choice: AMI-bucketed rent caps and income limits.
- Design choice: equity pricing as a per-credit input, not a yield input.
- What's left out (no Year 15 exit modeling, no Section 8 contracts).
- How to use the model in an affordable housing diligence workflow.
For an example of the engineering-essay format this article will follow, see how we engineered AQ-141, the Multifamily Opportunistic Pro Forma Model.
About the Model
TX-101 is an Institutional-tier multifamily LIHTC screener. Dual-mode for 4% and 9% deals, AMI-bucketed rent caps, per-credit equity pricing. Built for REPE shops underwriting affordable housing development opportunities.