Mill Valley 94941 · Strawberry · APN 043-224-09 · Unincorporated Marin
Zoned R1-B2 in Unincorporated Marin with likely ADU & SB 9 infill eligibility and zero mapped flood, fire, or fault hazard overlaps; benchmark value $2,255,000 ($1,984,000–$2,526,000).
Zoned R1-B2 supports ministerial ADU/JADU review plus SB 9 both two-unit development and ministerial urban lot split on a 11,761 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
Public building records show issued construction/renovation work on this parcel (2 total permits, latest Jun 24, 2021).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) (parcel APN)
43 substantial renovation & housing permits over 24 months (28.4 per 1,000 parcels vs. 16.4 citywide baseline) (#1 of 22 neighborhoods).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) (Strawberry)
Automated synthesis of indexed municipal, county, state, and federal public records — informational context only, not a formal appraisal, survey, or legal/tax determination.
$2,255,000
Benchmark range: $1,984,000 – $2,526,000
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)
Closest lead: New home at 218 Meda Ln (420 ft N, applied). Inspect timeline history before assuming near-term completion.
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · HCD APR (½-mile radius)
Sale triggers reassessment to 1.00% base + ~0.15% voter debt (~$2,199/mo). Confirm exact Mello-Roos / CFD special assessments on the county tax bill.
Source: CA Const. Art. XIIIA (Prop 13) · County Tax Collector
Since November 2024 within ½ mile: 6 permitted, 1 proposed or in review; 3 demolitions.
10 projects with a record in this window, grouped by us from permits and State housing reports. Units are as proposed on each project's latest record and counted at its current stage.
289 permits within ½ mile since November 2024
The map shows new construction, ADUs, demolitions, additions, and renovations. Routine systems work (roofs, HVAC, water heaters) is counted but not mapped. Unit counts are as stated on permits.
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Geography: permits located by parcel, ½ mile radius · Retrieved Nov 13, 2026
Public-records benchmark estimate combining Zillow Home Value Index (Data provided by Zillow), Census ACS 5-year estimates, parcel land-use/lot characteristics, and issued building permits. Not an official appraisal.
Permit counts, by the date issued (or applied, if not yet issued). Lot splits are planning cases, which we don't have.
We read public zoning and hazard maps against state law (ADUs: Gov. Code 66314; SB 9: Gov. Code 65852.21 and 66411.7). Local rules, title, tenancy history and site conditions can change the answer. Check with Unincorporated Marin's planning department before relying on it.
Sources: County of Marin GIS (MarinMap), Zoning (11 cities and unincorporated Marin) (retrieved Nov 13, 2026) · CAL FIRE Office of the State Fire Marshal, Fire Hazard Severity Zones in the State Responsibility Area (effective 2024-04-01) (retrieved Nov 9, 2026) · CAL FIRE Office of the State Fire Marshal, Fire Hazard Severity Zones in the Local Responsibility Area (map dated 2025-03-24) (retrieved Nov 9, 2026) · FEMA, National Flood Hazard Layer — flood hazard zones (retrieved Nov 9, 2026) · FEMA, National Flood Hazard Layer — FIRM panels (retrieved Nov 9, 2026) · California Geological Survey, Alquist-Priolo Earthquake Fault Zones (retrieved Nov 9, 2026) · Zoning classes: our classification of R1-B2 as single-family residential, checked against the zone description on Oct 24, 2026
Chronological history of building permit applications and issuances, snapshot-dated status changes, State housing entitlements, surrounding development within ½ mile, and area home-value trends.
Permit issued and active for 12.5 yr (first record May 20, 2014), with no completion or new permit record in 12.4 yr. · $2,000 declared valuation
Permit issued and active for 12.3 yr (first record Aug 7, 2014), with no completion or new permit record in 12.1 yr. · 1 unit · $1,000,000 declared valuation
Permit issued and active for 11.8 yr (first record Jan 27, 2015), with no completion or new permit record in 11.7 yr. · $35,000 declared valuation
Permit issued and active for 11.6 yr (first record Apr 23, 2015), with no completion or new permit record in 11.5 yr. · $8,000 declared valuation
Permit issued and active for 12.1 yr (first record Oct 2, 2014), with no completion or new permit record in 11.1 yr. · 1 unit · $631,507 declared valuation
Permit issued and active for 11.4 yr (first record Jun 15, 2015), with no completion or new permit record in 11.1 yr. · $250,000 declared valuation
Nearby roof replacement (102 Inez Pl): First appeared in published agency feed
Record B49099 · Detected between snapshots
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Snapshot diff within ½ mile
Nearby addition (adds square footage) (308 E Strawberry Dr): Declared valuation changed from 36900 to 41000
Record 94577 · Detected between snapshots
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Snapshot diff within ½ mile
Nearby remodel / interior alteration (144 Mission Dr): Contractor changed from (blank) to BOLT DOWN THE BAY AREA
Record 182696 · Detected between snapshots
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Snapshot diff within ½ mile
Nearby hvac / heat pump (201 Seminary Dr (Building 3)): Description text was updated
Record 94631 · Detected between snapshots
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Snapshot diff within ½ mile
Nearby remodel / interior alteration (201 Seminary Dr (Building 3)): Declared valuation changed from 6000000 to (blank)
Record 94586 · Detected between snapshots
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Snapshot diff within ½ mile
Nearby remodel / interior alteration (201 Seminary Dr (Building 3)): Description text was updated
Record 94586 · Detected between snapshots
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Snapshot diff within ½ mile
Nearby hvac / heat pump (201 Seminary Dr (Building 3)): Description text was updated
Record 94631 · Detected between snapshots
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Snapshot diff within ½ mile
Nearby addition (adds square footage) (127 Reed Blvd): First appeared in published agency feed
Record 94633 · Detected between snapshots
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Snapshot diff within ½ mile
Nearby remodel / interior alteration (201 Seminary Dr (Building 3)): Description text was updated
Record 94586 · Detected between snapshots
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Snapshot diff within ½ mile
Nearby hvac / heat pump (201 Seminary Dr (Building 3)): First appeared in published agency feed
Record 94631 · Detected between snapshots
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Snapshot diff within ½ mile
Nearby remodel / interior alteration (427 E Strawberry Dr): First appeared in published agency feed
Record 182860 · Detected between snapshots
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Snapshot diff within ½ mile
Nearby remodel / interior alteration (201 Seminary Dr (Building 3)): Description text was updated
Record 94586 · Detected between snapshots
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Snapshot diff within ½ mile
Nearby electrical / panel (320 E Strawberry Dr): First appeared in published agency feed
Record B48978 · Detected between snapshots
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Snapshot diff within ½ mile
Nearby remodel / interior alteration (427 E Strawberry Dr): No longer present in latest agency feed
Record 94356 · Detected between snapshots
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Snapshot diff within ½ mile
Nearby remodel / interior alteration (263 Richardson Dr): No longer present in latest agency feed
Record 94402 · Detected between snapshots
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Snapshot diff within ½ mile
Cross-referenced intelligence from our historical development graph—connecting parcels, permits, entity-resolved builders, empirical review-time distributions, and neighborhood renovation trends.
Explore full Unincorporated Marin development graph →In "Applied" for 6.5 yr (since Apr 30, 2020), exceeding the 253d median and 686d 90th percentile for new single-family home permits in Unincorporated Marin (n=121). High-impact scale (1 housing unit, $850,000 declared valuation across 1 permit).
Active in "Issued" for 12.3 yr (first record Aug 7, 2014) with no new permit activity recorded in 12.1 yr. High-impact scale (1 housing unit, $1,000,000 declared valuation across 1 permit).
Active in "Issued" for 3.4 yr (first record Jun 5, 2023) with no new permit activity recorded in 16 mo. High-impact scale (1 housing unit, $1,493,000 declared valuation across 1 permit).
Active in "Applied" for 8.1 yr (first record Oct 3, 2018) with no new permit activity recorded in 8.1 yr. High-impact scale ($1,600,000 declared valuation across 1 permit).
In "Applied" for 7.7 yr (since Mar 14, 2019), exceeding the 253d median and 686d 90th percentile for new single-family home permits in Unincorporated Marin (n=121).
In "Applied" for 2 yr (since Oct 31, 2024), exceeding the 253d median and 686d 90th percentile for new single-family home permits in Unincorporated Marin (n=121).
Substantial improvements (additions, interior remodels, ADUs, commercial TI, and new builds) across 1,512 parcels
+52.9% YoY
City baseline: 16.4 / 1k
43 in trailing 24m
Includes 8 ADUs
| Builder / contractor | Primary specialty | Here / ½ mi | ½ mi valuation | Citywide 24m trend |
|---|---|---|---|---|
| Owner Builder | Remodel / interior alteration | 1 on parcel49 in ½ mi | $10,548,711 | 226 vs 240 prior−6% |
| Sunrun Installation Service | Solar / battery storage | 1 on parcel1 in ½ mi | $38,000 | 0 vs 0 prior |
| Regency General Contractors Recent nearby: 50 Barbaree Wy - Bldg 31 (Sep 8, 2015) | Remodel / interior alteration |
| Permit category | Sample (n) | 25th pct | Median (50th) | 75th pct | 90th pct | Recent 24m median |
|---|---|---|---|---|---|---|
| New single-family home | 121 | 166d | 253d | 456d | 686d | 211d(vs 273d prior) |
| New multifamily / condos / mixed-use | 21 | 272d | 292d | 293d | 313d | 293d(vs 197d prior) |
| New garage / accessory structureOn this parcel | 356 | 104d | 164d | 294d | 485d | 159d(vs 205d prior) |
HUD Small Area Fair Market Rent · ZIP 94941
HUD FY 2026 · 40th-percentile gross rentCensus ACS 5-year median gross rent (all bedroom counts combined):
Area home-value benchmarks (not an appraisal)
ZIP & neighborhood mediansUnder California Proposition 13, the seller's historical assessed value does not carry over to a buyer. On sale, the parcel is reassessed at the purchase price: 1.00% base rate ($22,550/yr) + local voter-approved bond debt ($3,383/yr) + fixed direct levies/Mello-Roos ($450/yr).
Insurance & hazard context:
Model adding a backyard ADU or garage conversion under California's Prop 13 blended new-construction assessment (existing house & land tax base stays intact; only ADU build cost is assessed) and SB 13 impact-fee rules.
−$128,505/yr
Cash needed: $496,100
NOI: $8,325/yr
P&I: $11,403/mo
For $0/mo net cash flow
At $3,950/mo gross rent
| Scenario | Assumptions | Year 1 Rent | Year 1 Cash Flow | Cash-on-Cash | Break-Even Rent | Year 5 Cash Flow |
|---|---|---|---|---|---|---|
| Conservative | −8% starting rent, +3% vacancy, +3% combined maintenance/CapEx, 1.5%/yr rent growth | $3,634/mo | −$11,163/mo | -27.0% | $19,216/mo | −$11,198/mo |
| Base (your inputs) | Your entered assumptions, 3.0%/yr rent growth | $3,950/mo | −$10,709/mo | -25.9% | $17,786/mo | −$10,520/mo |
| Optimistic (cap-limited) | +6% starting rent, 3% vacancy, 4.5%/yr rent growth (capped by AB 1482 ceiling of 8.6%/yr) | $4,187/mo | −$10,448/mo | -25.3% | $17,373/mo | −$10,005/mo |
Rental regulatory context (informational only — not legal advice):
California AB 1482 (Tenant Protection Act, Civ. Code § 1947.12) caps annual rent increases at 5% + local CPI (max 10%) on covered properties.
6.8kw Rooftop Photovoltaic & Energy Storage System
Addn; Rmdl; Covrd Porch; Decks; Garage Reconfig
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Geography: parcel (APN) · Retrieved Nov 13, 2026 · Received and issued dates come from the County of Marin. The county publishes no final or expired status, so an issued permit stays 'Issued' after the work is done.
No housing activity reported to the State for this parcel (2018–2025 reports).
Source: California HCD, Housing Element Annual Progress Report — Table A2 · Geography: project (parcel) · Retrieved Nov 9, 2026 · From Unincorporated Marin's Housing Element Annual Progress Reports. A project can appear in several report years as it moves from entitlement to permit to completion.
Source: County of Marin GIS (MarinMap), Zoning (11 cities and unincorporated Marin) · Geography: zoning district polygon at parcel point · Retrieved Nov 13, 2026
0.27 acres
Assessor's classification for assessment purposes. This is not zoning.
312 RICHARDSON DR
Source: County of Marin GIS (MarinMap), Parcels · Geography: parcel · Retrieved Nov 13, 2026
Search by parcel number 043-224-09. Assessed value is not market value.
Search by parcel number 043-224-09 (Marin County Tax Collector)
Permits issued in unincorporated Marin in the past 48 months. Each city keeps its own records.
The official flood hazard map for this location. Our reading of it is under What could be built here.
This site does not show owner names.
| 148 in ½ mi |
| $2,097,503 |
| 0 vs 0 prior |
| Owner Recent nearby: 219 Reed Blvd (Mar 5, 2025) | Remodel / interior alteration | 35 in ½ mi | $1,146,201 | 25 vs 15 prior+67% |
| Kerr Construction Recent nearby: 427 E Strawberry Dr (Nov 2, 2026) | Remodel / interior alteration | 6 in ½ mi | $1,056,000 | 2 vs 2 prior |
| Lek Enterprises Recent nearby: 450 E Strawberry Dr Units 13 (Nov 25, 2019) | Remodel / interior alteration | 6 in ½ mi | $152,000 | 0 vs 11 prior−100% |
| Centric Construction Recent nearby: 201 Seminary Drive Bldg 4 (Jan 28, 2026) | Demolition | 4 in ½ mi | $315,000 | 2 vs 0 prior |
| Juan Calmell Recent nearby: 129 Reed Blvd (Jul 21, 2014) | Demolition | 4 in ½ mi | $21,600 | 0 vs 0 prior |
| Swinerton Builders Recent nearby: 2 Belvedere Pl #310 (May 31, 2017) | Commercial tenant improvement | 3 in ½ mi | $1,155,000 | 0 vs 0 prior |
| Singlepoint Design Build Recent nearby: 421 E Strawberry Dr (Mar 24, 2020) | Addition (adds square footage) | 3 in ½ mi | $800,000 | 2 vs 0 prior |
| Accessory dwelling unit (new or conversion) | 298 | 120d | 204d | 331d | 549d | 214d(vs 181d prior) |
| Addition (adds square footage) | 316 | 103d | 160d | 249d | 440d | 157d(vs 167d prior) |
| Remodel / interior alteration | 1,054 | 36d | 83d | 148d | 266d | 112d(vs 77d prior) |
| Commercial tenant improvement | 81 | 99d | 148d | 233d | 443d | 152d(vs 150d prior) |
| Solar / battery storageOn this parcel | 2,977 | 0d | 0d | 0d | 2d | 0d |
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Computed from issued permits with recorded application and issuance dates over the trailing 60 months. Categories with fewer than 20 permits are excluded.