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Deal Analysis · Tool · Calculator

The Honest STR Underwriting Calculator

A short-term rental doesn’t earn one number — it earns a range. Enter a deal and this returns a conservative, expected, and optimistic case side by side, so you see cash flow, cash-on-cash, and DSCR across the year you might actually have — not a single flattering figure.

Matt NunnMatt Nunn · Founder, Builders Finance
Tool · Deal Analysis

The most dangerous number in underwriting is a single one. Enter the deal below. Rather than one projection, the calculator flexes occupancy and rate to show a conservative, expected, and optimistic year — because a deal that only works in the optimistic column hasn’t penciled.

How the cases are built. The expected column uses your inputs as entered. The conservative column drops occupancy by 10 points and rate by 10% — a plausible soft year. The optimistic column adds 5 points of occupancy and 5% on rate. Operating expenses and financing hold constant across all three. Read the conservative column first: if the deal goes cash-flow-negative or falls below a 1.0 DSCR there, it’s riding on the forecast.

This is a 15-minute quick-screen, not a full model — a fast read on whether a deal is worth deeper work. The four metrics it returns are the ones weighed in Does This Deal Actually Pencil?; the full method is The STR Deal Underwriting Manual. For the occupancy floor specifically, use the Break-Even Occupancy Calculator.

The Builders Finance Underwriting Method

Source it — trace every number to real evidence, not a headline.
Haircut it — discount for the year you’ll actually have; round revenue down, costs up.
Record it — value, source, and haircut, in The Assumptions Ledger.
Stress it — move the numbers that matter to their downside before you trust them.

Educational information only — not individualized tax, legal, or investment advice. Results are an illustrative model based on the inputs you provide, not a projection or a recommendation.

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