127 Greenbrae Boardwalk
Greenbrae 94904 · Greenbrae · Unincorporated Marin · Coordinates: 37.94171, -122.50900
Executive Verdict · Public-Records Synthesis
Zoned RSP-4.36-BFC in Unincorporated Marin with likely ministerial ADU eligibility and mapped FEMA AE flood due diligence; benchmark value $2,163,000 ($1,903,000–$2,423,000).
Upsides & Opportunities
- ✓ Ministerial ADU / JADU pathway likely eligible
Zone RSP-4.36-BFC allows residential use qualifying for ministerial ADU review under state law.
Source: Unincorporated Marin zoning · CA Gov. Code 66314
- ✓ Documented permitted upgrades (+$112,500 contributory est.)
Public building records show issued construction/renovation work on this parcel (4 total permits, latest Oct 12, 2026).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) (parcel APN)
Watchouts & Due Diligence
- ! FEMA Special Flood Hazard Area (AE, all of the lot of lot)
Zone AE: 1% annual chance flood (Special Flood Hazard Area) overlaps this parcel. Expect mandatory flood insurance for federally backed loans and floodplain elevation/mitigation rules for new units or SB 9 applications.
Source: FEMA National Flood Hazard Layer (parcel polygon)
- ! Delayed or open permit activity on this parcel
Addition (adds square footage) (182305): Issued after 18 mo (3.5× the 160d median) — slower than 90% of addition (adds square footage) permits in Unincorporated Marin (median 160d, 90th pct 440d, n=316).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) (review-time benchmark)
- ! 4 slow or stalled nearby projects within ½ mile
Closest lead: New home (0.19 mi W, entitled). Inspect timeline history before assuming near-term completion.
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · HCD APR (½-mile radius)
- ! Year 1 Prop 13 tax reset (~$25,325/yr at $2,163,000)
Sale triggers reassessment to 1.00% base + ~0.15% voter debt (~$2,110/mo). Confirm exact Mello-Roos / CFD special assessments on the county tax bill.
Source: CA Const. Art. XIIIA (Prop 13) · County Tax Collector
Parcel & Assessor
- Lot size:
- 5,663 sq ft (0.13 ac)
- Assessor use:
- Single-Resid. - Improved
- Addresses on lot:
- 127 GREENBRAE BOARDWALK
Zoning & Land Use
RSP-4.36-BFC — Residential Single Family Planned (Unincorporated Marin)
State Housing Pathways Screen (ADU & SB 9)
- ADU or junior ADULikely eligible
Zoned RSP-4.36-BFC (single-family residential): state law allows ADUs where homes are allowed.
- SB 9: two homes on the lotPossible, with conditions
Zoned RSP-4.36-BFC, a single-family residential zone. FEMA Special Flood Hazard Area (Zone AE) covers all of the lot: the project must meet the National Flood Insurance Program floodplain standards, or the lot needs a map revision.
- SB 9: split into two lotsPossible, with conditions
Zoned RSP-4.36-BFC, a single-family residential zone. The lot is 5,663 sq ft by the assessor, room for two lots of at least 1,200 sq ft, each at least 40% of the original. FEMA Special Flood Hazard Area (Zone AE) covers all of the lot: the project must meet the National Flood Insurance Program floodplain standards, or the lot needs a map revision.
Mapped Hazard Zones on This Lot
- CAL FIRE Fire Hazard Severity Zone
- Not in a State-mapped fire hazard severity zone
- FEMA National Flood Hazard Layer
- Zone AE: 1% annual chance flood (Special Flood Hazard Area) (all of the lot) · FIRM panel 06041C0459F, effective March 16, 2016
- CGS Alquist-Priolo Earthquake Fault Zone
- Not in an Alquist-Priolo Earthquake Fault Zone
Surrounding Rent & Value Benchmarks (Public Records)
Range: $1,903,000 – $2,423,000 · Status: Off market
HUD Small Area FMR (ZIP 94904) · FY 2026
Studio $2,260 · 1BR $2,710 · 2BR $3,280 · 3BR $4,190 · 4BR $4,340
Developments Deserving Closer Investigation & Active Area Builders
- Addition (adds square footage) (182305) (Issued)On this parcel
Issued after 18 mo (3.5× the 160d median) — slower than 90% of addition (adds square footage) permits in Unincorporated Marin (median 160d, 90th pct 440d, n=316).
- New home (Entitled)0.19 mi W
In "Entitled" for 5.1 yr (since Oct 1, 2021), exceeding the 253d median and 686d 90th percentile for new single-family home permits in Unincorporated Marin (n=121).
- General repair (171996) (Issued)On this parcel
Issued after 10 mo (3.7× the 83d median) — above the 75th percentile for general repair permits in Unincorporated Marin (median 83d, 75th pct 181d, n=693).
- New home at 193 Sir Francis Drake Blvd E (Applied)0.22 mi N
Active in "Applied" for 14 mo (first record Aug 29, 2025) with no new permit activity recorded in 10 mo. High-impact scale ($109,000,000 declared valuation across 2 permits).
Entity-resolved builders & contractors in ½ mile: Mid Cal Construction (1 on parcel, 1 in ½ mi · General repair); Cl Construction (1 on parcel, 1 in ½ mi · Addition (adds square footage)); Ernest Ongaro And Sons (1 on parcel, 1 in ½ mi · HVAC / heat pump); Cls Electric (1 on parcel, 1 in ½ mi · Electrical / panel); Owner Builder (7 in ½ mi · Demolition).
Permit & Project History on This Parcel (4 permits, 0 grouped projects)
| Record # | Category | Status | Applied / Issued | Valuation | Description |
|---|---|---|---|---|---|
| B48737 | Electrical / panel | Issued | Iss. Oct 12, 2026 | $4,500 | Service Upgrade |
| 182305 | Addition (adds square footage) | Issued | Iss. Aug 19, 2026 | $150,000 | Addition @ Rear Of Cottage; Rmdl Laundry & Bath; Reroof; Heat Pump; Siding; Windows/Doors In Area Of Rmdl/Addn *Extended… |
| B44238 | HVAC / heat pump | Issued | Iss. Oct 7, 2025 | $10,811 | ADD NEW HEAT PUMP — Mechanical Appliance |
| 171996 | General repair | Issued | Iss. Jul 27, 2022 | $274,345 | Raise House, Shed, And Deck Above B F E- *Structural Elevation Project* |