NYC Co-op Affordability Finder

Reverse-engineer your max purchase price from your financial profile
1 Account Balances
Account Balance ($) Closing? Reserve % Closing Cash Reserve Value
Closing Cash (Closing? = ✓) — wired at closing to cover the down payment + closing costs. Check any account you can fully liquidate on closing day.
Reserve Value (balance × Reserve %) — counts toward the board's post-close cushion. Boards typically apply a 70–80% haircut on brokerage and exclude retirement accounts — set Reserve % to 0% for accounts your board ignores.

Defaults reflect a typical NYC co-op buyer (~$150K income, age 35–42) based on 2024–25 Federal Reserve SCF, Fidelity, and Vanguard data.

Total Closing Cash
—
Total Reserve Value
—
2 Income & Existing Debts
$
$
$
3 Mortgage Assumptions
%
yrs
%
4 Co-op Requirements
mo
%
$
5 Closing Costs
Fixed Costs
$
$
$
$
$
—
Variable Costs
%
Your Max Affordable Price
$—
Binding constraint: —
Model a specific price:
$
Cash Waterfall
Down Payment —
Fixed Closing Costs —
Variable Closing Costs —
Total at Close —
Avail for DP + CC (Closing ✓) —
DP + CC Surplus / (Deficit) —
Maintenance Reserve (24 mo) —
Mortgage Reserve (24 mo) —
Total Cash Needed —
Total for Reserves (all weighted) —
Reserves Surplus / (Deficit) —
Post-close for reserves —
Post-close reserve months —
Monthly Costs
Mortgage (P+I) —
Maintenance —
Total Monthly Housing —
Effective DTI —
Feasibility Check
✓ Cash —
✓ DTI —
✓ Reserves —

Two constraints, one limit

This calculator finds the lower of two maximum prices:

  • Cash / Reserves: Your assets are split into two pools. Only accounts with Closing? checked can cover the down payment and closing costs — these are wired at closing. All accounts (weighted by Reserve %) count toward the post-close reserve cushion — most boards require 12 months of carrying costs (maintenance + mortgage), though conservative buildings ask for 24+. Both pools must be sufficient for a deal to work.
  • DTI / Income: Your total monthly housing payment (mortgage P+I + maintenance + other debts) must stay within the board's debt-to-income ratio limit on your gross monthly income. Most NYC boards use 25–30% DTI.

Whichever constraint produces the lower max price is your binding limit — you can't spend more than both allow simultaneously.

Closing? checkbox vs. Reserve %

Each account has two independent settings. Closing? — check this for any account you can fully liquidate and wire on closing day (cash, HYSA, brokerage you plan to sell). The full balance then counts toward the down payment and closing costs. Reserve % — the fraction of the balance your board credits toward post-closing reserves. Boards typically credit 100% for cash and HYSA, 70–80% for brokerage (market-volatility haircut), and 0% for retirement accounts (401k, IRA, Roth IRA), which appear on Schedule D of the REBNY financial statement rather than as liquid reserves. You can check Closing? on a brokerage account while setting its Reserve % to 80% — meaning you'd wire the full amount at closing but only 80% counts toward your post-close cushion in the board's eyes.

Mansion tax is tiered

New York's mansion tax applies to co-op purchases just as it does to condos — you're buying shares in a corporation, but the tax follows the consideration paid. It starts at 1% on purchases of $1M–$2M and steps up to 3.9% above $25M. The tax is not marginal: crossing a tier raises the entire bill, so $999,999 owes $0 while $1,000,001 owes ~$10,000. The calculator applies this automatically and shows it as a separate line in the closing cost waterfall. The variable rate field covers loan origination fees and any buyer-side flip tax only — do not add mansion tax there. Flip tax (typically 1–3% of sale price) is usually paid by the seller, but some buildings charge the buyer — check the proprietary lease.

This is an estimate — verify everything

Co-op board requirements vary significantly. Your building may have stricter DTI limits, different reserve requirements, or an unusual flip tax structure. Always confirm numbers with a licensed mortgage broker (for rate locks and DTI qualification) and a real estate attorney (for closing costs and the proprietary lease).