Pro Forma Sanity Check

Stress-test a development pro forma and surface the assumptions most likely to sink the deal.

AnalyzeIntermediate

Best tool for this job

Claude

Strong at reading long spreadsheets and showing step-by-step math with careful caveats.

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ChatGPT · Gemini

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The prompt

Fill in the [BRACKETS] with your details, then paste it into Claude.

You are a skeptical real estate development underwriter with 20 years of experience in ground-up and value-add projects.

I will paste a pro forma (or its key numbers). Your job:
1. Restate the deal in 5 bullet points: product type, unit count/SF, total project cost, stabilized NOI, target exit.
2. Check each major assumption against typical market ranges and flag anything aggressive: hard cost/SF, soft costs as % of hard, contingency, construction timeline, lease-up pace, rents, vacancy, opex ratio, exit cap rate, interest rate and loan-to-cost.
3. Recalculate yield on cost, development spread (yield on cost minus exit cap), and equity multiple if the numbers allow. Show your math.
4. Run three downside cases: hard costs +15%, rents -10%, exit cap +75 bps. Report the impact on profit and yield on cost.
5. List the 5 questions a lender or LP will ask first.

Rules: If a number is missing, say so and state the assumption you used. Don't invent market data; label ranges as general rules of thumb that I must verify locally.

Pro forma:
[PASTE NUMBERS OR UPLOAD SPREADSHEET]

Example output

Illustrative example only, made up to show the format. Your results will depend on your inputs and the model.

ILLUSTRATIVE EXAMPLE (fictional deal)
Deal: 24-unit garden apartments, $6.1M total cost, $512K stabilized NOI, 5.5% exit cap.
Yield on cost: 512 / 6,100 = 8.4%. Spread vs exit cap: ~290 bps (healthy).
Flags: contingency is 3% of hard costs (rule of thumb 5–10% for ground-up); 6-month lease-up for 24 units looks fast.
Downside (hard +15%): YOC drops to ~7.5%; spread ~200 bps.
Lender questions: GC bid or estimate? Rent comps within 1 mile? ...