21 Via Cheparro
Greenbrae 94904 · Kentfield · Unincorporated Marin · Coordinates: 37.95080, -122.52644
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 $2,483,000 ($2,185,000–$2,781,000).
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 32,278 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 (+$14,080 contributory est.)
Public building records show issued construction/renovation work on this parcel (2 total permits, latest Mar 3, 2021).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) (parcel APN)
- ✓ Above-average reinvestment in Kentfield
103 substantial renovation & housing permits over 24 months (40.9 per 1,000 parcels vs. 16.3 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: 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 33 Bretano Way (0.13 mi SW, 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 (~$29,005/yr at $2,483,000)
Sale triggers reassessment to 1.00% base + ~0.15% voter debt (~$2,417/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:
- 32,278 sq ft (0.74 ac)
- Assessor use:
- Single-Resid. - Improved
- Addresses on lot:
- 21 VIA CHEPARRO
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 32,278 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: minimal flood hazard (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: $2,185,000 – $2,781,000 · 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
- New home at 33 Bretano Way (Issued)0.13 mi SW
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).
- Accessory dwelling unit at 24 Bretano Way (Applied)0.11 mi SW
In "Applied" for 4.6 yr (since Apr 11, 2022), exceeding the 253d median and 686d 90th percentile for new single-family home permits in Unincorporated Marin (n=121).
- Demolition at 17 La Cuesta Dr (Applied)0.12 mi SE
In "Applied" for 12.4 yr (since Jul 8, 2014), exceeding the 55d median and 261d 90th percentile for demolition permits in Unincorporated Marin (n=130).
- New home at 16 La Cuesta Dr (Applied)0.14 mi SE
In "Applied" for 12.3 yr (since Aug 12, 2014), 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: R Scott Swann Gen Contr (1 on parcel, 1 in ½ mi · Remodel / interior alteration); Reyes Heating And Air (1 on parcel, 1 in ½ mi · HVAC / heat pump); Owner Builder (38 in ½ mi · Remodel / interior alteration); Owner (28 in ½ mi · Remodel / interior alteration); Goltermann Construction (6 in ½ mi · Demolition).
Permit & Project History on This Parcel (2 permits, 0 grouped projects)
| Record # | Category | Status | Applied / Issued | Valuation | Description |
|---|---|---|---|---|---|
| B25035 | HVAC / heat pump | Issued | Iss. Mar 3, 2021 | $19,000 | Furnace and A/C replacement — Replace Mechanical Appliance |
| 156057 | Remodel / interior alteration | Issued | Iss. Jul 24, 2017 | $40,000 | Kitch Remod - Express |