Renting by the room can double a property's income — if you underwrite the higher expense load honestly. Built by an operator running 8 rooms in Atlanta: this calculator prices in the utilities, turnover, and vacancy that room-rental actually carries. Tuned for St. Louis, MO: the rent defaults below start at the metro's real FY2025 HUD Fair Market Rent — edit anything to match your deal.
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Official HUD Fair Market Rents for the St. Louis, MO-IL HUD Metro FMR Area. Use these as a sanity check against any listing's rent claims — if a pro-forma assumes rents far above these, ask why.
| Studio | 1 BR | 2 BR | 3 BR | 4 BR |
|---|---|---|---|---|
| $951/mo | $984/mo | $1,215/mo | $1,570/mo | $1,806/mo |
Source: U.S. Department of Housing & Urban Development, FY2025 Fair Market Rents. FMRs are gross-rent estimates at the 40th percentile — solid floor benchmarks; well-located or renovated properties often rent above them.
A calculator answers one strategy with the numbers you type. The AgenticREI analyzer answers all six — buy & hold, rent-by-room, fix & flip, wholesale, STR, and BRRRR — from just an address in St. Louis or anywhere else. It pulls the property records and market rents itself, flags where the listing's claims disagree with the data, and gives you a straight BUY, NEGOTIATE, or PASS.
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