I always start with the current rent. Compare that with market. If it's vacant then I would see how many nearby are for rent. From there work backward with the expenses.
Linda — you're asking the right question, and the answer is: think like the underwriter, because the underwriter only cares about one ratio.
For DSCR, income is the LOWER of (a) your actual lease or (b) the appraiser's market-rent opinion. The underwriter takes that number and divides it by PITI — principal, interest, taxes, insurance. That's the DSCR. Most lenders want 1.0 or better, meaning the rent covers the payment.
So before you apply, run it yourself: market rent (be conservative — use the appraiser's likely number, not your best case), divided by the full PITI at today's rate. If it clears 1.0 with a cushion, it's worth pursuing. If it's under 1.0, some programs will still do it (no-ratio-required options exist) — but know which bucket you're in before you apply, because it changes the lender list and the pricing.
Operating expenses matter for YOUR analysis (vacancy, maintenance, capex decide whether the deal actually makes money), but they don't enter the DSCR math — the lender's formula is rent vs. PITI, full stop.
What rent and payment are you looking at? Happy to run the ratio with you — Dan
Asking this before applying is the right order. Most of the surprises in a DSCR file come from the payment side of the ratio, not the rent side. The tax figure on a listing is the seller's current bill, and in a lot of counties it gets reassessed toward the new purchase price, so estimate taxes on what you're actually paying. Get a real landlord insurance quote early too, especially in a flood zone or near the coast, because premiums have moved more than rents in many markets lately. If there's an HOA, most DSCR lenders add the dues to the monthly payment before they run the ratio. A ratio is only as reliable as the weakest number in it, and that's usually the one copied off the listing.
@Linda Murray Start with all three, because they work together. Verify market rent using recent comparable leases and, if occupied, the actual lease. Then estimate realistic vacancy and operating costs—taxes, insurance, repairs, capex, management, HOA dues, and any owner-paid utilities—to determine whether the property truly cash flows.
Next, compare the rent with the proposed principal, interest, taxes, insurance, and association payments using the lender's exact DSCR formula, since requirements vary. A rental is worth pursuing when it clears the lender's threshold with a healthy cushion, still produces an acceptable return after full expenses, and survives stress tests for lower rent, vacancy, repairs, and higher insurance or taxes. If approval depends on optimistic rent or perfect operations, the margin is probably too thin.
Hey Linda - you can just run the DSCR. This is super simple math. Plug it into chatgpt / claude ... or you can use something like our calculator here too.
The higher the number above 1 the better ... ideally you want to be 1.2 or higher.