Forest Knolls 94933 · Forest Knolls · APN 168-041-42 · Unincorporated Marin
Zoned RA-B4-SGV in Unincorporated Marin with likely ministerial ADU eligibility and mapped CAL FIRE high fire hazard severity zone (state responsibility area) due diligence; benchmark value $988,000 ($869,000–$1,107,000).
Zone RA-B4-SGV allows residential use qualifying for ministerial ADU review under state law.
Source: Unincorporated Marin zoning · CA Gov. Code 66314
On-parcel permit history is indexed through Mar 2, 2021, 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)
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)
Automated synthesis of indexed municipal, county, state, and federal public records — informational context only, not a formal appraisal, survey, or legal/tax determination.
18 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
$988,000
Benchmark range: $869,000 – $1,107,000
Located in a mapped Fire Hazard Severity Zone. Expect Chapter 7A ignition-resistant building standards, defensible-space inspections, and stricter property insurance underwriting.
Source: CAL FIRE FHSZ (map Apr 1, 2024)
Closest lead: Accessory dwelling unit at 5 Barranca Rd (0.37 mi W, 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 (~$984/mo). Confirm exact Mello-Roos / CFD special assessments on the county tax bill.
Source: CA Const. Art. XIIIA (Prop 13) · County Tax Collector
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.
No ADU or new-home permits recorded within ¼ mile in this window.
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 RA-B4-SGV 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 12.3 yr (first record Aug 11, 2014), with no completion or new permit record in 11.8 yr. · 1 unit · $222,000 declared valuation
Permit issued and active for 11.7 yr (first record Feb 26, 2015), with no completion or new permit record in 8.7 yr. · 1 unit · $79,000 declared valuation
In "Applied" for 7.8 yr (since Feb 7, 2019), with no new permit record in 7.8 yr. · 1 unit · $187,000 declared valuation
Permit issued and active for 7.9 yr (first record Dec 6, 2018), with no completion or new permit record in 7.7 yr. · 1 unit · $118,000 declared valuation
Latest published Zillow Home Value Index (ZHVI) update
Changed from $810,654 in September 2025 to $863,910 in September 2026.
Source: Zillow Home Value Index (ZHVI) · Data provided by Zillow · Geography: ZIP 94933 (not a parcel appraisal)
Annual ZIP 94933 home-value index checkpoint
Changed from $856,056 in September 2024 to $810,654 in September 2025.
Source: Zillow Home Value Index (ZHVI) · Data provided by Zillow · Geography: ZIP 94933 (not a parcel appraisal)
Annual ZIP 94933 home-value index checkpoint
Changed from $861,171 in September 2023 to $856,056 in September 2024.
Source: Zillow Home Value Index (ZHVI) · Data provided by Zillow · Geography: ZIP 94933 (not a parcel appraisal)
Annual ZIP 94933 home-value index checkpoint
Changed from $910,322 in September 2022 to $861,171 in September 2023.
Source: Zillow Home Value Index (ZHVI) · Data provided by Zillow · Geography: ZIP 94933 (not a parcel appraisal)
Annual ZIP 94933 home-value index checkpoint
Changed from $874,038 in September 2021 to $910,322 in September 2022.
Source: Zillow Home Value Index (ZHVI) · Data provided by Zillow · Geography: ZIP 94933 (not a parcel appraisal)
Annual ZIP 94933 home-value index checkpoint
Changed from $758,678 in September 2020 to $874,038 in September 2021.
Source: Zillow Home Value Index (ZHVI) · Data provided by Zillow · Geography: ZIP 94933 (not a parcel appraisal)
HVAC / heat pump permit application filed (B25020)
Current status: Issued
Ductless Minisplit -- 18K FUJITSU OUTDOOR, 12K INDOOR, 9K INDOOR — Replace Mechanical Appliance · Declared valuation: $13,581 · Contractor: Bigham Services Inc
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Geography: parcel
HVAC / heat pump permit issued (B25020)
Recorded status: Issued
Ductless Minisplit -- 18K FUJITSU OUTDOOR, 12K INDOOR, 9K INDOOR — Replace Mechanical Appliance · Declared valuation: $13,581 · Contractor: Bigham Services Inc
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Geography: parcel
228 Arroyo Rd A K A · 1 unit · $118,000 valuation
Records span Dec 6, 2018 to Mar 19, 2019 (1 permit).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) & HCD APR (grouped project within ½ mile)
5 Barranca Rd · 1 unit · $187,000 valuation
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) & HCD APR (grouped project within ½ mile)
94 Tamal Rd · 1 unit · $79,000 valuation
Records span Feb 26, 2015 to Feb 27, 2018 (1 permit).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) & HCD APR (grouped project within ½ mile)
42 Arroyo Rd · 1 unit · $222,000 valuation
Records span Aug 11, 2014 to Feb 2, 2015 (1 permit).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) & HCD APR (grouped project 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 7.8 yr (since Feb 7, 2019), exceeding the 253d median and 686d 90th percentile for new single-family home permits in Unincorporated Marin (n=121).
Active in "Issued" for 11.7 yr (first record Feb 26, 2015) with no new permit activity recorded in 8.7 yr.
Active in "Issued" for 7.9 yr (first record Dec 6, 2018) with no new permit activity recorded in 7.7 yr.
Active in "Issued" for 12.3 yr (first record Aug 11, 2014) with no new permit activity recorded in 11.8 yr.
| Builder / contractor | Primary specialty | Here / ½ mi | ½ mi valuation | Citywide 24m trend |
|---|---|---|---|---|
| Bigham Services | HVAC / heat pump | 1 on parcel1 in ½ mi | $13,581 | 0 vs 0 prior |
| Owner Builder Recent nearby: 230 Arroyo Rd (Mar 19, 2019) | Accessory dwelling unit (new or conversion) | 2 in ½ mi | $389,000 | 226 vs 240 prior−6% |
| Owner Recent nearby: 210 Tamal Rd (Jan 6, 2016) | Addition (adds square footage) |
| 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) |
| Accessory dwelling unit (new or conversion) | 298 | 120d | 204d | 331d | 549d | 214d(vs 181d prior) |
| Addition (adds square footage) |
HUD Small Area Fair Market Rent · ZIP 94933
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 ($9,900/yr) + local voter-approved bond debt ($1,485/yr) + fixed direct levies/Mello-Roos ($450/yr).
Mapped hazard zone insurance context on this parcel:
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.
−$36,662/yr
Cash needed: $217,800
NOI: $23,410/yr
P&I: $5,006/mo
For $0/mo net cash flow
At $4,150/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 | $3,818/mo | −$3,532/mo | -19.5% | $8,748/mo | −$3,471/mo |
| Base (your inputs) | Your entered assumptions, 3.0%/yr rent growth | $4,150/mo | −$3,055/mo | -16.8% | $8,097/mo | −$2,759/mo |
| Optimistic (cap-limited) | +6% starting rent, 3% vacancy, 4.5%/yr rent growth (capped by AB 1482 ceiling of 8.6%/yr) | $4,399/mo | −$2,781/mo | -15.3% | $7,909/mo | −$2,217/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.
Ductless Minisplit -- 18K FUJITSU OUTDOOR, 12K INDOOR, 9K INDOOR — Replace Mechanical Appliance
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
2.15 acres
Assessor's classification for assessment purposes. This is not zoning.
251 TAMAL RD
Source: County of Marin GIS (MarinMap), Parcels · Geography: parcel · Retrieved Nov 13, 2026
Search by parcel number 168-041-42. Assessed value is not market value.
Search by parcel number 168-041-42 (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.
| 2 in ½ mi |
| $200,000 |
| 25 vs 15 prior+67% |
| Hope Construction Recent nearby: 42 Arroyo Rd (Feb 2, 2015) | New single-family home | 1 in ½ mi | $222,000 | 0 vs 1 prior |
| Brownco Construction And Dev Recent nearby: 145 Tamal Rd (Apr 2, 2020) | Commercial tenant improvement | 1 in ½ mi | $150,000 | 0 vs 1 prior |
| 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) |
| HVAC / heat pumpOn this parcel | 2,946 | 0d | 0d | 0d | 0d | 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.