DealMath: Rental Property Calculator

DealMath is a rental property calculator that runs right on the listing page. Open a property on Zillow, Redfin, or Realtor.com and the panel fills itself in with the price, property taxes, and HOA from the page. Add the rent you expect and you get the full deal analysis in seconds. No spreadsheet, and no copying numbers between tabs. WHAT YOU GET (FREE) Monthly cash flow, cash-on-cash return, and cap rate Mortgage payment, NOI, cash needed to close, DSCR, the 1% rule, gross rent multiplier, and break-even occupancy Deal grade from A to F, based on targets you set yourself for cash flow, cash-on-cash, cap rate, and DSCR Fields read from the page are marked, estimates are marked, and every field is editable Your rate, down payment, and expense assumptions are remembered between listings Save up to 3 deals, with notes and a status (Watching, Visiting, Offered, Passed) WHO IT IS FOR Landlords screening their next rental, house hackers checking a duplex, BRRRR investors, and anyone who wants the numbers before they book a showing. PRO ($9/MONTH, OR SAVE WITH THE ANNUAL PLAN) Max offer price: set a goal and see the highest price that still hits it BRRRR mode: rehab, refinance, cash left in the deal, and cash recovered Projections: equity, total return, and cash flow over time House-hack and multi-unit mode: add rents per unit and remove the unit you live in More loan types: FHA, seller financing, and interest-only, plus points Rent memory: reuse the rent you typed for a ZIP code and bedroom count Price change tracking on saved listings, a one-page print summary of any deal, unlimited saved deals, side-by-side comparison ranked by cash-on-cash, CSV export, and rate and rent stress tests PRIVACY No account, no ads, no tracking. Your saved deals and settings stay in your browser. The extension only contacts Gumroad to check a Pro license key. Full policy: swensondigital.carrd.co DealMath is not affiliated with Zillow, Redfin, or Realtor.com. Results are estimates, not financial advice. Verify taxes, insurance, and rent before making an offer.