204 Helen Ave
Mill Valley 94941 · Almonte · Unincorporated Marin · Coordinates: 37.88299, -122.52505
Executive Verdict · Public-Records Synthesis
Zoned RMP-40 in Unincorporated Marin with likely ministerial ADU eligibility and zero mapped flood, fire, or fault hazard overlaps; benchmark value $2,109,000 ($1,856,000–$2,362,000).
Upsides & Opportunities
- ✓ Ministerial ADU / JADU pathway likely eligible
Zone RMP-40 allows residential use qualifying for ministerial ADU review under state law (5 ADU permits permitted within ¼ mile in 36 months).
Source: Unincorporated Marin zoning · CA Gov. Code 66314
- ✓ Documented permitted upgrades (+$30,228 contributory est.)
Public building records show issued construction/renovation work on this parcel (6 total permits, latest Feb 24, 2023).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) (parcel APN)
Watchouts & Due Diligence
- ! Mapped flood awareness zone (Zone X: minimal flood hazard)
all of the lot of the parcel intersects Zone X: minimal flood hazard. Outside mandatory federal SFHA insurance rules, but check local drainage and finished-floor requirements.
Source: FEMA National Flood Hazard Layer (parcel polygon)
- ! 6 slow or stalled nearby projects within ½ mile
Closest lead: New home at 222 Beryl St (0.16 mi NW, 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 (~$24,704/yr at $2,109,000)
Sale triggers reassessment to 1.00% base + ~0.15% voter debt (~$2,059/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:
- 5,968 sq ft (0.14 ac)
- Assessor use:
- Single-Resid. - Improved
- Addresses on lot:
- 204 HELEN AVE
Zoning & Land Use
RMP-40 — Residential Multiple Planned (Unincorporated Marin)
State Housing Pathways Screen (ADU & SB 9)
- ADU or junior ADULikely eligible
Zoned RMP-40 (multifamily residential): state law allows ADUs where homes are allowed. On a multifamily lot the state allowance is different: ADUs in non-living space of the building, plus up to eight detached ADUs.
- SB 9: two homes on the lotUnlikely
Zoned RMP-40 (multifamily residential), not a single-family residential zone.
- SB 9: split into two lotsUnlikely
Zoned RMP-40 (multifamily residential), not a single-family residential zone.
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: minimal flood hazard (all 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: $1,856,000 – $2,362,000 · 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
- New home at 222 Beryl St (Issued)0.16 mi NW
Active in "Issued" for 11.9 yr (first record Dec 23, 2014) with no new permit activity recorded in 10 yr. High-impact scale (1 housing unit, $900,000 declared valuation across 1 permit).
- New home at 217 Cleveland Ave (Issued)0.23 mi NW
Active in "Issued" for 9.7 yr (first record Feb 21, 2017) with no new permit activity recorded in 2.3 yr. High-impact scale (1 housing unit, $875,000 declared valuation across 1 permit).
- New home at 334 Dolan Ave (Issued)0.29 mi SW
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).
- Accessory dwelling unit at 131 Yale Ave A (Issued)0.4 mi NW
Active in "Issued" for 4.8 yr (first record Jan 19, 2022) with no new permit activity recorded in 3.4 yr. High-impact scale (1 housing unit, $1,000,000 declared valuation across 1 permit).
Entity-resolved builders & contractors in ½ mile: Owner Builder (2 on parcel, 82 in ½ mi · Remodel / interior alteration); Owner (1 on parcel, 47 in ½ mi · Remodel / interior alteration); Enviro Heating And Air Conditioning (1 on parcel, 1 in ½ mi · HVAC / heat pump); Murdock Bryan (1 on parcel, 1 in ½ mi · Solar / battery storage); Marin County Roofing (1 on parcel, 1 in ½ mi · Roof replacement).
Permit & Project History on This Parcel (6 permits, 0 grouped projects)
| Record # | Category | Status | Applied / Issued | Valuation | Description |
|---|---|---|---|---|---|
| B32743 | Solar / battery storage | Issued | Iss. Feb 24, 2023 | $28,000 | New rooftop PV system flush-mounted with central inverter, Meter Bud Panel utility connection and no battery storage. |
| B29280 | Roof replacement | Issued | Iss. Apr 4, 2022 | $12,000 | T/O existing tar/gravel roof and replace with gray colored Modified bitumen cap sheet. No new sheathing required. — ReRo… |
| B29203 | HVAC / heat pump | Issued | Iss. Mar 25, 2022 | $40,885 | Install a new 4 ton Bryant Evolution 20 SEER heat pump. — Replace Mechanical Appliance |
| B29148 | Plumbing / water heater / sewer | Issued | Iss. Mar 21, 2022 | $1,800 | Replace existing tank water heater with new tankless water heater. — New Circuits / Outlets; Replace Plumbing Fixtures(s… |
| 154684 |