246 Flamingo Rd
Mill Valley 94941 · Tamalpais · Unincorporated Marin · Coordinates: 37.87954, -122.52642
Executive Verdict · Public-Records Synthesis
Zoned R1-B1 in Unincorporated Marin with likely ministerial ADU eligibility and mapped FEMA AE flood due diligence; benchmark value $2,072,000 ($1,823,000–$2,321,000).
Upsides & Opportunities
- ✓ Ministerial ADU / JADU pathway likely eligible
Zone R1-B1 allows residential use qualifying for ministerial ADU review under state law (9 ADU permits permitted within ¼ mile in 36 months).
Source: Unincorporated Marin zoning · CA Gov. Code 66314
- ✓ 6 documented municipal building permits on file
On-parcel permit history is indexed through Jul 17, 2026, letting you verify roof, HVAC, electrical, or structural work against seller disclosures.
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) (parcel APN)
- ✓ Above-average reinvestment in Tamalpais
50 substantial renovation & housing permits over 24 months (20.5 per 1,000 parcels vs. 16.4 citywide baseline) (#3 of 22 neighborhoods).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) (Tamalpais)
Watchouts & Due Diligence
- ! FEMA Special Flood Hazard Area (AE, about 15% of the lot of lot)
Zone AE: regulatory floodway (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) (144188): Issued after 2.6 yr (5.8× 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 commercial building at 201 Flamingo Rd (aka 205) (0.1 mi N, issued). 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 (~$24,278/yr at $2,072,000)
Sale triggers reassessment to 1.00% base + ~0.15% voter debt (~$2,023/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:
- 6,142 sq ft (0.14 ac)
- Assessor use:
- Single-Resid. - Improved
- Addresses on lot:
- 246 FLAMINGO RD
Zoning & Land Use
R1-B1 — Residential Single Family (Unincorporated Marin)
State Housing Pathways Screen (ADU & SB 9)
- ADU or junior ADULikely eligible
Zoned R1-B1 (single-family residential): state law allows ADUs where homes are allowed.
- SB 9: two homes on the lotPossible, with conditions
Zoned R1-B1, a single-family residential zone. FEMA regulatory floodway covers about 15% of the lot: SB 9 requires a no-rise certification.
- SB 9: split into two lotsPossible, with conditions
Zoned R1-B1, a single-family residential zone. The lot is 6,142 sq ft by the assessor, room for two lots of at least 1,200 sq ft, each at least 40% of the original. FEMA regulatory floodway covers about 15% of the lot: SB 9 requires a no-rise certification.
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: regulatory floodway (Special Flood Hazard Area) (about 15% of the lot); Zone AE: 1% annual chance flood (Special Flood Hazard Area) (about 85% of the lot) · FIRM panel 06041C0469F, 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: $1,823,000 – $2,321,000 · Status: Off market
HUD Small Area FMR (ZIP 94941) · FY 2026
Studio $2,730 · 1BR $3,270 · 2BR $3,960 · 3BR $5,060 · 4BR $5,240
Developments Deserving Closer Investigation & Active Area Builders
- Addition (adds square footage) (144188) (Issued)On this parcel
Issued after 2.6 yr (5.8× the 160d median) — slower than 90% of addition (adds square footage) permits in Unincorporated Marin (median 160d, 90th pct 440d, n=316).
- Electrical / panel (144187) (Issued)On this parcel
Issued after 2.6 yr — slower than 90% of electrical / panel permits in Unincorporated Marin (median 0d, 90th pct 2d, n=3,019).
- New commercial building at 201 Flamingo Rd (aka 205) (Issued)0.1 mi N
Active in "Issued" for 11.7 yr (first record Feb 17, 2015) with no new permit activity recorded in 11.2 yr. High-impact scale ($3,938,400 declared valuation across 3 permits).
- New home at 334 Dolan Ave (Issued)0.21 mi NW
Active in "Issued" for 8.2 yr (first record Sep 5, 2018) with no new permit activity recorded in 8 yr. High-impact scale (1 housing unit, $759,000 declared valuation across 1 permit).
Entity-resolved builders & contractors in ½ mile: Owner Builder (1 on parcel, 69 in ½ mi · Remodel / interior alteration); Owner (2 on parcel, 48 in ½ mi · Remodel / interior alteration); Mc Leran (1 on parcel, 1 in ½ mi · Roof replacement); Solarcity (1 on parcel, 1 in ½ mi · Solar / battery storage); Tesla Energy Operations (1 on parcel, 1 in ½ mi · Other).
Permit & Project History on This Parcel (6 permits, 0 grouped projects)
| Record # | Category | Status | Applied / Issued | Valuation | Description |
|---|---|---|---|---|---|
| B47523 | Other | Issued | Iss. Jul 17, 2026 | $2,500 | — |
| B47508 | Roof replacement | Issued | Iss. Jul 16, 2026 | $19,600 | ReRoofing; With Electronic Inspection |
| 146971 | New garage / accessory structure | Issued | Iss. May 5, 2015 | $3,000 | Add Pergola Over Deck - Bwop T.D. 3/17/15 |
| 144188 | Addition (adds square footage) | Issued | Iss. Sep 18, 2014 | $58,725 | Cvrt Grge To Offce, Rmdl Bdrm, Addn (52) Gasline To Fire Insert (58) Wndws Skylite **Ext To 6/10/15 /15. |
| 144187 | Electrical / panel | Issued | Iss. Sep 18, 2014 | $4,000 |