Short-term rental income looks simple from the outside — set a nightly rate, watch the bookings roll in. But underwriting an STR responsibly means separating rate from occupancy, combining them correctly, and knowing exactly how empty your calendar can get before the property stops paying for itself. Four metrics do that job.
Master these before you buy, because STR revenue is far more volatile than a 12-month lease. The same property can have a phenomenal July and a dead January, and your analysis has to survive both.
ADR: Average Daily Rate
ADR is your average nightly rate across booked nights. It is not your listed rate — it is what guests actually paid, averaged over the nights that actually booked. Weekend premiums, seasonal peaks, and last-minute discounts all wash into this single number.
The mistake new hosts make is anchoring ADR to hope instead of data. Pull comps from short-term rental data services like AirDNA or Rabbu, filter to properties that genuinely match yours — bedroom count, capacity, amenities, and micro-location — and use the realistic middle of the range, not the best-performing outlier with a hot tub and a lake view you do not have.
Occupancy: Share of Nights Booked
STR occupancy is the percentage of available nights that get booked. A property booked 200 nights out of 365 runs about 55% occupancy — which, not coincidentally, is a common sustainability bar in the industry. Markets and properties routinely running 55%+ occupancy tend to support viable STR businesses; below that, you need an unusually strong ADR to compensate.
Occupancy and ADR trade off against each other. Drop your price and occupancy rises; raise it and occupancy falls. That is exactly why neither number alone tells you much.
RevPAN: Revenue Per Available Night
RevPAN multiplies the two together: ADR x occupancy. A listing with a $250 ADR at 60% occupancy earns $150 per available night. A listing at $180 and 85% earns $153 — effectively the same revenue with a completely different strategy.
RevPAN is the great equalizer for comparing properties and pricing strategies. When you are evaluating a market or testing assumptions, RevPAN times 365 gives you estimated annual gross revenue in one step. It also keeps you honest: a fantasy $400 ADR means nothing if the occupancy that comes with it is 25%.
Break-Even Occupancy: Your Margin of Safety
The most important defensive metric is break-even occupancy — the occupancy level at which revenue covers your operating costs plus the mortgage payment. Estimate it by dividing your total annual costs by (ADR x 365).
Say your mortgage, utilities, insurance, supplies, platform fees, and cleaning costs total $54,000 a year and your ADR is $250. Break-even occupancy is $54,000 ÷ ($250 x 365) ≈ 59%. Now compare that to what the market actually delivers. If comparable listings run 65% occupancy and you need 59% just to break even, one soft season or a new competitor puts you underwater. If the market runs 70% and you break even at 45%, you have real cushion.
A wide gap between market occupancy and break-even occupancy is what separates a durable STR from a stressful one.
Put the Metrics Together
A quick underwriting flow: get ADR and occupancy comps from data services, multiply them into RevPAN for a revenue estimate, then compute break-even occupancy against your full cost stack and check the cushion. The free Shouldirefi Deal Analyzer has an STR strategy that walks through exactly this — enter your ADR, occupancy, and cost assumptions and it estimates revenue, cash flow, and your break-even point so you can stress-test the deal before you commit.
All figures are estimates for informational purposes only — not financial advice. Consult a qualified professional before making financial decisions.