Rejected
3121-3125 Castro St
This one never reached the math. What stopped it is below.
94131 · San Francisco
mixed-use (commercial financing)
Underwritten as of 2026-08-18 · record v10
Published at our defaults: loses to the S&P, behind by $389,917 · S&P breakeven 2.3% first-pass screen
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This record was published before we began recording the mortgage rate behind each verdict, so it cannot be re-run at your numbers.
Why we rejected it
- mixed-use (commercial financing)
Rejected when we checked the listing itself.
Property facts
| Asking price | $1,710,000 |
|---|---|
| Units | 2 |
| Beds / baths | 6 / 5 |
| Square feet | 3,154 |
| Year built | 1931 |
| Property type | Multi-Family |
Unit count verified: 3 units, corroborated by county assessor records and the listing itself.
Nearby projects on our catalyst watch:
- Chenery Street Village · 0.1 mi · open today
- Glen Park BART soft-site disposition (55-space surface parking lot) · 0.1 mi · proposed
- Glen Park Community Plan 6-8 story upzone (Dec 9, 2025 amendment) · 0.1 mi · open today
From the 2026-08-18 screen: 400 scanned · 34 beat the S&P at our defaults · 366 rejected.
If the market turns
Modeled appreciation is an assumption, so we replayed this deal against history: every 10-year window in the federal house-price index for San Francisco County (41 windows), each one swapping its actual price path in for our modeled appreciation.
| History replay | Years | Ends vs the never-buy path |
|---|---|---|
| Worst window | 1989→1999 | −$1,679,744 |
| Median window | 1991→2001 | +$260,871 |
| Best window | 1996→2006 | +$3,024,713 |
17 of the 41 windows ended behind the never-buy path.
Replay the 2001 downturn as it hit this area and the deal ends year 10 $769,886 behind the never-buy path; the deepest point comes in year 8, $946,978 behind. The replay holds rent growth to the local legal cap the whole way down.
These windows track San Francisco County as a whole. Within the county, individual ZIPs' realized 10-year outcomes typically differed from the county's by about ±0.6 points/yr — one zip-decade in ten differed by ±1.8 points/yr or more, and the largest gap since 1975 was 7.4 points/yr. A specific building varies more than its ZIP, not less.
Where these numbers come from
Of the 10 inputs behind this analysis, 1 traces to evidence (our listing feed, area comps, county records).
- Purchase price: an unclassified source · corroborated
- Rent while you live in one unit: an unclassified source · no independent witness
- Rent after you move out: an unclassified source · no independent witness
- The rent you would pay on the never-buy path: an unclassified source · no independent witness
- Property tax rate: an unclassified source · no independent witness
- Unit count: county assessor records · corroborated
A standing convention is a deliberate modeling choice we apply to every deal. We flag it rather than dress it up as evidence.
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Record v10 · engine aafb236 · profile fha-house-hack