←kenny sandon
proprise (yc s23) · 2024–2026 · founding product & customer success
primer: ai agents that underwrite deals
Grew to 60% of company revenue, driving ARR from ~$150K to over $700K. Used by 50+ firms managing $150B+ in commercial real estate.
Every underwriting interview surfaced the same complaint: analysts were retyping numbers from offering memos, rent rolls, and P&Ls into Excel, deal after deal.
While our CTO was traveling, I built the first version of Primer myself, an Excel plugin that could underwrite real deals. We had a paying customer within a month.
From there I ran product and stayed every customer's primary technical contact. I designed in Figma, spec'd features in Linear, and shipped thousands of lines of production code with coding agents.
- 8–10 extraction agents per customer, built for their own document formats
- Every agent tested against real deals before the customer went live; 99%+ extraction accuracy
- Ten eval passes per template, since most errors were variance, not repeated mistakes
- Cheap models for simple extractions, frontier reasoning for messy files: cost and processing time both halved
- Review screens put the model's reasoning beside each answer, with one-click corrections it remembered
- Customers tripled underwriting volume; one cut per-deal work from 90 minutes to 10