2390 Mar East St
Tiburon 94920 · Unincorporated Tiburon · Unincorporated Marin · Coordinates: 37.87687, -122.44387
Executive Verdict · Public-Records Synthesis
Zoned R2 in Unincorporated Marin with likely ministerial ADU eligibility and mapped FEMA VE flood due diligence; benchmark value $2,784,000 ($2,450,000–$3,118,000).
Upsides & Opportunities
- ✓ Ministerial ADU / JADU pathway likely eligible
Zone R2 allows residential use qualifying for ministerial ADU review under state law (2 ADU permits permitted within ¼ mile in 36 months).
Source: Unincorporated Marin zoning · CA Gov. Code 66314
- ✓ Documented permitted upgrades (+$6,720 contributory est.)
Public building records show issued construction/renovation work on this parcel (10 total permits, latest Nov 4, 2025).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) (parcel APN)
Watchouts & Due Diligence
- ! FEMA Special Flood Hazard Area (VE, about 5% of the lot of lot)
Zone VE: 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
General repair (177780): Issued after 19 mo (7.0× the 83d median) — slower than 90% of general repair permits in Unincorporated Marin (median 83d, 90th pct 328d, n=693).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) (review-time benchmark)
- ! 3 slow or stalled nearby projects within ½ mile
Closest lead: New home (0.47 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 (~$32,466/yr at $2,784,000)
Sale triggers reassessment to 1.00% base + ~0.15% voter debt (~$2,706/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:
- 2,526 sq ft (0.06 ac)
- Assessor use:
- Multiple-Resid. - Improved
- Addresses on lot:
- 2390 MAR EAST ST; 2392 MAR EAST ST
Zoning & Land Use
R2 — Residential Two Family (Unincorporated Marin)
State Housing Pathways Screen (ADU & SB 9)
- ADU or junior ADULikely eligible
Zoned R2 (two-family residential): state law allows ADUs where homes are allowed.
- SB 9: two homes on the lotCan't tell
Zoned R2 (two-family residential): we can't tell whether it counts as a single-family zone for SB 9. Residential Two Family.
- SB 9: split into two lotsCan't tell
Zoned R2 (two-family residential): we can't tell whether it counts as a single-family zone for SB 9. Residential Two Family.
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 VE: 1% annual chance flood (Special Flood Hazard Area) (about 5% of the lot); Zone X: minimal flood hazard (about 95% of the lot) · FIRM panel 06041C0489E, 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: $2,450,000 – $3,118,000 · Status: Off market
HUD Small Area FMR (ZIP 94920) · FY 2026
Studio $2,820 · 1BR $3,380 · 2BR $4,100 · 3BR $5,230 · 4BR $5,420
Developments Deserving Closer Investigation & Active Area Builders
- General repair (177780) (Issued)On this parcel
Issued after 19 mo (7.0× the 83d median) — slower than 90% of general repair permits in Unincorporated Marin (median 83d, 90th pct 328d, n=693).
- Other (176678) (Issued)On this parcel
Issued after 11 mo — slower than 90% of other permits in Unincorporated Marin (median 0d, 90th pct 71d, n=1,562).
- Other (169822) (Issued)On this parcel
Issued after 2 mo — above the 75th percentile for other permits in Unincorporated Marin (median 0d, 75th pct 1d, n=1,562).
- New home (Entitled)0.47 mi W
In "Entitled" for 2.3 yr (since Aug 13, 2024), exceeding the 253d median and 686d 90th percentile for new single-family home permits in Unincorporated Marin (n=121).
Entity-resolved builders & contractors in ½ mile: Owner Builder (4 on parcel, 12 in ½ mi · Accessory dwelling unit (new or conversion)); Owner (2 on parcel, 4 in ½ mi · Windows / doors / siding); Marron Construction (1 on parcel, 2 in ½ mi · General repair); Tesla Energy Operations (1 on parcel, 1 in ½ mi · Solar / battery storage); First Class Water Heaters (1 on parcel, 1 in ½ mi · HVAC / heat pump).
Permit & Project History on This Parcel (10 permits, 0 grouped projects)
| Record # | Category | Status | Applied / Issued | Valuation | Description |
|---|---|---|---|---|---|
| B44676 | Electrical / panel | Issued | Iss. Nov 4, 2025 | $300 | Install two (2) LED directional fixtures, Focus Industries Model DL17 in white finish, mounted on the front façade. Each… |
| 177780 | General repair | Issued | Iss. Oct 7, 2024 | $3,500 | Seawall; Repair Stairs/Ladder & Foundation |
| B38203 | Windows / doors / siding | Issued | Iss. May 28, 2024 | $2,800 | Repair/reinforce EXISTING concrete pad for existing foundation damaged due to storms and repair/replace existing rusted … |
| 176678 | Other | Issued | Iss. May 21, 2024 | $650 | Repair (E) Deck Railing W/ Termite Damage |
| 173072 | Electrical / panel | Issued |