Martin County presents a basis-versus-validation tension: buyers who can verify rentable condition and insurance should investigate, while buyers relying on quick resale or stable operating costs should be cautious. Zillow’s 2026-06 county median home value was $131,892, up 3.15% year over year, while FHFA’s 2025 annual repeat-transaction HPI fell 0.79%. These are different methods and vintages, not a combined growth measure.
Income underwriting is the main gap. No market asking rent is published, so gross yield cannot be computed. HUD’s two-bedroom FMR of $925 per month is a payment standard, not measured market rent, and cannot substitute for it. The effective property-tax rate is 1.07%; without published rent, its burden relative to revenue cannot be assessed. That county-level rate does not establish a parcel tax bill. Underwriters need current achieved or asking rents, vacancy, utilities, insurance, and repair evidence before testing coverage.
At the 2026-06 Realtor.com MLS listing-market snapshot, median marketing time was 86 days and 19.84% of listings had price reductions. Those are visible-supply and seller-concession indicators, not sales prices or standalone proof of buyer demand. Tax-return migration records show net migration of 43 households, and incoming movers’ average AGI exceeded outgoing movers’ by a calculated $2,367; that modest positive flow merits address-level demand checks. Investors represented 8 of 153 purchase mortgages, a limited but identifiable competitor set.
Hurricane is the dominant hazard; modeled annual climate loss is 0.28% of building value, a modeled exposure rather than a property-specific insurance quote. Validate flood and wind zone, replacement cost, deductibles, exclusions, and available premiums before fixing expenses. The record does not publish market rent, sale-price trends, vacancy, insurance cost, parcel condition, or lease terms; without them an underwriter cannot establish gross yield, expense coverage, exit liquidity, or hazard-adjusted cash flow. County aggregates also cannot resolve neighborhood or property variation.