89 Corte Cayuga
Greenbrae 94904 · Kentfield · Unincorporated Marin · Coordinates: 37.94779, -122.51932
Executive Verdict · Public-Records Synthesis
Zoned R1-B2 in Unincorporated Marin with likely ADU & SB 9 infill eligibility and zero mapped flood, fire, or fault hazard overlaps; benchmark value $2,376,000 ($2,091,000–$2,661,000).
Upsides & Opportunities
- ✓ ADU & SB 9 infill pathways screen as likely eligible
Zoned R1-B2 supports ministerial ADU/JADU review plus SB 9 both two-unit development and ministerial urban lot split on a 12,894 sq ft lot. Local precedent is active with 1 ADU permit within ¼ mile over the last 36 months.
Source: Unincorporated Marin zoning · CA Gov. Code 66314 & 65852.21
- ✓ Documented permitted upgrades (+$24,840 contributory est.)
Public building records show issued construction/renovation work on this parcel (4 total permits, latest Aug 7, 2025).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) (parcel APN)
- ✓ Above-average reinvestment in Kentfield
104 substantial renovation & housing permits over 24 months (41.3 per 1,000 parcels vs. 16.4 citywide baseline) (#7 of 22 neighborhoods).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) (Kentfield)
Watchouts & Due Diligence
- ! Mapped flood awareness zone (Zone X: 0.2% annual chance flood hazard (shaded X))
about 96% of the lot of the parcel intersects Zone X: 0.2% annual chance flood hazard (shaded X). Outside mandatory federal SFHA insurance rules, but check local drainage and finished-floor requirements.
Source: FEMA National Flood Hazard Layer (parcel polygon)
- ! Delayed or open permit activity on this parcel
New garage / accessory structure (142000): Issued after 2.2 yr (4.9× the 164d median) — slower than 90% of new garage / accessory structure permits in Unincorporated Marin (median 164d, 90th pct 485d, n=356).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) (review-time benchmark)
- ! 5 slow or stalled nearby projects within ½ mile
Closest lead: 1000 Drakes Landing Road (0.23 mi S, 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 (~$27,774/yr at $2,376,000)
Sale triggers reassessment to 1.00% base + ~0.15% voter debt (~$2,315/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:
- 12,894 sq ft (0.30 ac)
- Assessor use:
- Single-Resid. - Improved
- Addresses on lot:
- 89 CORTE CAYUGA
Zoning & Land Use
R1-B2 — Residential Single Family (Unincorporated Marin)
State Housing Pathways Screen (ADU & SB 9)
- ADU or junior ADULikely eligible
Zoned R1-B2 (single-family residential): state law allows ADUs where homes are allowed.
- SB 9: two homes on the lotLikely eligible
Zoned R1-B2, a single-family residential zone.
- SB 9: split into two lotsLikely eligible
Zoned R1-B2, a single-family residential zone. The lot is 12,894 sq ft by the assessor, room for two lots of at least 1,200 sq ft, each at least 40% of the original.
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 X: 0.2% annual chance flood hazard (shaded X) (about 96% of the lot); Zone X: minimal flood hazard (about 4% 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: $2,091,000 – $2,661,000 · 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
- 1000 Drakes Landing Road (Entitled)0.23 mi S
In "Entitled" for 2.1 yr (since Oct 8, 2024), exceeding the 292d median and 313d 90th percentile for new multifamily / condos / mixed-use permits in Unincorporated Marin (n=21). High-impact scale (19 housing units, 4 deed-restricted affordable across 0 permits).
- New garage / accessory structure (142000) (Issued)On this parcel
Issued after 2.2 yr (4.9× the 164d median) — slower than 90% of new garage / accessory structure permits in Unincorporated Marin (median 164d, 90th pct 485d, n=356).
- New home at 33 Bretano Way (Issued)0.46 mi W
Active in "Issued" for 19 mo (first record Apr 11, 2025) with no new permit activity recorded in 14 mo. High-impact scale (1 housing unit, $750,000 declared valuation across 1 permit).
- Demolition at 10 Corte De Sabla (Applied)450 ft NW
In "Applied" for 5.7 yr (since Mar 2, 2021), exceeding the 55d median and 261d 90th percentile for demolition permits in Unincorporated Marin (n=130).
Entity-resolved builders & contractors in ½ mile: Owner (1 on parcel, 12 in ½ mi · Remodel / interior alteration); Solarcraft Services (1 on parcel, 1 in ½ mi · Solar / battery storage); Renewable Electric (1 on parcel, 1 in ½ mi · Solar / battery storage); Stephen Curley Roofing (1 on parcel, 1 in ½ mi · Roof replacement); Owner Builder (16 in ½ mi · Remodel / interior alteration).
Permit & Project History on This Parcel (4 permits, 0 grouped projects)
| Record # | Category | Status | Applied / Issued | Valuation | Description |
|---|---|---|---|---|---|
| B43384 | Solar / battery storage | Issued | Iss. Aug 7, 2025 | $45,800 | NEW FLUSH MOUNTED PV SYSTEM WITH NEW BATTERY STORAGE, GRID TIED HYBRID INVERTERS,TO EXISTING MAIN SERVICE PANEL & NEW SU… |
| B41054 | Roof replacement | Issued | Iss. Jan 30, 2025 | $19,720 | Remove existing composition roofing. Replace with Class A composition roofing per manufacturers specifications. Install … |
| 150454 | Solar / battery storage | Issued | Iss. Jan 21, 2016 | $28,000 | P V Sys 6.161 K W - Express***Expired |
| 142000 | New garage / accessory structure | Issued | Iss. Mar 24, 2014 | $140,000 | Addition And Replace Garage Roof (Framing ) T.D. 3/5/2012 * Pd For Appl Ext To 1/17/14 * Application Extended To 1/17/15… |