3845 Bloomfield Rd — Findings
Property: 3845 Bloomfield Rd, Sebastopol (Twin Hills), CA 95472 APN: 025-100-006 Owner: MOSIMAN STEVEN T TR & MOSIMAN HELEN C TR Pulled: 2026-05-11
TL;DR
A 51.15-acre LEA-zoned (Land Extensive Agriculture, 160-ac minimum) parcel on the south side of Bloomfield Rd just SE of the Burnside Rd intersection, ~0.5 mi east of the in-laws’ parcel at 4201 Bloomfield Rd and ~1 mi east of the Hanson / Bloomfield Farms parcel at 4707. The parcel sits in the Twin Hills CDP, in Twin Hills Union Elementary and West Sonoma Union High districts (a stronger school footprint than the in-laws’ Shoreline JUSD). It carries the OAK (Valley Oak Habitat) and SR (Scenic Resources) combining districts but not the RC50/50 riparian overlay — i.e. no designated stream cuts the parcel. Hazards are benign: Moderate FHSZ in Cal Fire SRA, neither floodway nor floodplain, Very Low liquefaction, mixed landslide rating. Groundwater Zone 2 (major recharge). No Williamson Act contract.
The parcel is owned by Steven Thomas Mosiman (age 68; President of Sheehan Construction, Inc., a Napa/Sebastopol-based residential framer doing ~$42M/yr) and his wife Helen C. Mosiman, as co-trustees of their family trust. The Mosimans live in another Sebastopol-area property a few miles from the subject parcel — not Los Angeles, contrary to the briefing premise. (Their residential address is filed publicly as Steve’s CA Secretary of State officer address for Sheehan Construction; retrievable via CorporationWiki or bizfileonline.sos.ca.gov.) Steve co-founded Sheehan Construction with Tom Sheehan in November 1998. Their two sons are both professional motocross figures: Michael Mosiman (born 7/16/1999 in Sebastopol; currently rides for Monster Energy Star Racing Yamaha 250SX West) and Josh Mosiman (older brother, former pro Supercross/MX, now Assistant Editor at Motocross Action Magazine).
Permit Sonoma carries five records for the parcel, all Engineering-side, no Building/Septic/Code-Enforcement. Four of the five are about a motocross track: GRD09-0106 (2009) → GRD12-0080 (2012) → R/S 13-126 (boundary survey, 2013) → GRD15-0104 (2015, described as ”@ 100%”). Adobe Associates of Santa Rosa engineered all three grading permits; Sheehan Construction was the contractor on the 2009 driveway encroachment. All three grading permits expired without being finaled — the track exists and is permit-graded, but the permits never closed out. There is no code-enforcement case on file. The 1925, 804-sf assessor-listed dwelling pre-dates the Permit Sonoma system entirely.
2025 net taxable value: $1,421,692 (Land $1,291,631 + Improvements $130,061). Mosimans acquired the parcel 2008-10-24 for $1,100,000 (Doc # 2008R096841); trust transfer 2009-06-15 (Doc # 2009R057779). Holding period ~17.6 years. The property is not currently listed on any MLS aggregator. The single most relevant comp is your in-laws’ Dec 2025 acquisition of 4201 Bloomfield Rd (BERTY ENTERPRISE LLC) at $2,485,000 / 46.15 ac = $53,847/acre — applied to 3845’s 51.15 acres yields a direct extrapolation of ~$2.76M. The Wells / 5 Wells Vineyard adjacent at 3545 Bloomfield is also actively listed at $6.5M (reduced from $10.5M, 38% cut), signaling some softening at the high end of the corridor. Working market value estimate: $2.5M–$3.0M most likely clearing — capped by the LEA B6 160 zoning constraint (new primary residence not permitted on this sub-160-ac parcel, though the existing legal nonconforming dwelling may be maintained/replaced).
The asset’s real value, beyond the dirt, is proximity — to the in-laws at 4201, to the Hanson/Bloomfield Farms operation at 4707, and to a school district + corridor + zoning class that make this an unusually clean LEA hold. The owner relationship is the constraint: this is a NorCal construction-industry family that built, surveyed, and engineered the parcel themselves over ~17+ years. An off-market approach has to respect that.
Identity & ownership
| Legal owner | Mosiman Steven T Tr & Mosiman Helen C Tr (Steven Thomas + Helen C. Mosiman, co-trustees of a family trust) |
| Trustees | Steven Thomas Mosiman (age 68); Helen C. Mosiman (~55) |
| Residence | A separate Sebastopol-area property (per Steve’s CA SoS officer-address filing on Sheehan Construction — retrievable via CorporationWiki or bizfileonline.sos.ca.gov) |
| Steven’s profession | President / CEO, Sheehan Construction, Inc. — Co-founded Nov 1998 with Tom Sheehan. General contractor, residential framing, $42M revenue, ~500 employees. CA SoS Doc # 2139847 (incorporated 1999-05-26). CSLB licenses 767115 & 809970 active. |
| Sheehan Construction Napa office | 477 Devlin Rd Ste 108, Napa, CA 94558 — (707) 603-2610 |
| Sheehan Construction Sebastopol office | 1418 Gravenstein Hwy S, Sebastopol — (707) 823-8479 |
| Business partner | Thomas F. Sheehan (VP/Secretary/CFO/Registered Agent/CSLB RMO) — Sebastopol-based |
| Sons | Josh Mosiman (older — pro racer turned MXA Assistant Editor; @joshmosiman); Michael Mosiman (born 7/16/1999 Sebastopol, active pro 250SX West rider for Monster Energy Star Racing Yamaha; @_michaelmosiman) |
| Acquisition | 2008-10-24 for $1,100,000 (Sonoma County Recorder Doc # 2008R096841) |
| Trust transfer | 2009-06-15 (Doc # 2009R057779) — into the Mosiman Family Trust |
| Prior owner | Tom Birse / “Tom Birse et al” (consistent with adjacent 3858 Bloomfield ownership; deed-image verification at https://crarecords.sonomacounty.ca.gov/Web/) |
| Holding period | ~17.6 years as of May 2026 |
Land facts
| Acreage | 51.15 acres (~2,221,560 sf) |
| Zoning | LEA B6 160, OAK SR (Land Extensive Agriculture, 160-acre minimum density; Valley Oak Habitat + Scenic Resources combining districts) |
| Land use | LEA 160 |
| Assessor use code | 0541 — Pasture With Residence |
| Williamson Act | No contract — flexibility for a buyer, but no current ag tax break |
| Area & Specific Plan | Petaluma Dairy Belt Area Plan |
| Planning Area | 6 — Sebastopol; Supervisorial District 2 |
| Tax Rate Area | 159003 |
| Schools | Twin Hills Union Elementary + West Sonoma Union High (stronger ratings than neighboring Shoreline JUSD) |
| Fire District | Gold Ridge FPD |
| Fire Hazard Severity Zone | Moderate (Cal Fire State Responsibility Area) |
| Liquefaction | Very Low Susceptibility |
| Landslide | Mixed — “Few Landslides, Mostly Landslide” (the basis for engineered grading requirements) |
| Floodway / floodplain | Neither (No / No) |
| Groundwater zone | Zone 2 — major natural recharge |
| Groundwater subbasin | Wilson Grove Formation Highlands — Very Low priority (no SGMA constraint expected near-term) |
| Wet Weather Zone | D — Sebastopol |
| Farmland classification | Grazing Land, Other Land |
| NRCS Soils | LoD, LoE, LsE, SnD2 (Los Osos / Spreckels clay-loams; sloping; moderate-strong erosion hazard) |
| California Tiger Salamander overlay | No |
| Coordinates | 38.336511, -122.828512 (parcel center, county GIS) |
Improvements & infrastructure
Permit Sonoma carries five records for the parcel; the Sonoma assessor records three structures totaling 2,352 sf. No septic permit, no well permit, no AEX, no ZPE, no code enforcement.
Assessor-recorded structures (total 2,352 sf)
| Structure | Size | Year built | Notes |
|---|---|---|---|
| Principal residence | 804 sf | 1925 | 2 BR / 1 BA, Class CD040C (low/avg) |
| Detached garage | 396 sf | 1971 | — |
| “Other structure” | 1,152 sf | 1971 | The substantive secondary structure — likely a barn/equipment shed or second outbuilding from the 1971 build-out. Worth a site walk to identify. |
The 1971 structures came in 46 years after the original farmhouse and 37 years before the Mosiman acquisition — i.e., the prior owner (likely Birse) added them. The Mosimans haven’t added any permitted structures since acquiring; their only additions are the driveway and motocross track.
Permit-recorded improvements (2009 onward)
- Driveway entrances (south side of Bloomfield Rd, 0.05 mi and 0.11 mi SE of Burnside Rd) — installed/upgraded under ENC09-0030 (2009, Finaled) by Sheehan Construction Inc (Steve’s own company).
- Engineered motocross track — graded under three sequential permits: GRD09-0106 (Adobe Associates engineer Steven R. Brown, 2009) → GRD12-0080 (2012) → GRD15-0104 (2015, work described as ”@ 100%”). All three expired but not finaled. The track is the principal post-2008 “improvement.”
- Surveyed boundary (R/S 13-126, Book 762 Maps 11) — surveyor Aaron R. Smith, filed Dec 2013, map approved.
Grandfathered systems
- Original 1925 septic and well are grandfathered — no Permit Sonoma SEP/SEV records. Any new SFD or expanded dwelling triggers fresh well-yield testing and a new SEP application.
The asset stack reads as a working family training ground: 1925 farmhouse + 1971 garage + 1971 outbuilding + 2009 driveway + 2009–2015 motocross track + 2013 boundary survey. No event venue, no commercial ag, no cannabis, no equestrian, no vineyard.
Permit narrative arc (2009 → 2026)
- Feb 2009 (ENC09-0030): Driveway encroachment permit pulled by Steven Thomas Mosiman with Sheehan Construction Inc as contractor — installs the new south-side driveway and upgrades the existing one to county standards. Finaled. This is the only record of Steven personally on a permit; the trust takes over after.
- June 2009 (GRD09-0106): Adobe Associates (engineer Steven R. Brown) pulls the first grading permit: “GRADING FOR MOTO-CROSS TRACK.” Expires.
- June 2012 (GRD12-0080): Adobe Associates re-pulls to “complete” the 2009 grading. Expires.
- Dec 2013 (R/S 13-126): Aaron R. Smith files a Record of Survey for “MOSIMAN,” recorded in Book 762 Maps 11. Map approved.
- June 2015 (GRD15-0104): Now under the trust (“Mosiman Steven T Tr”), final grading permit to “complete” the prior work — described as ”@ 100%“. Expires (final-status date 2018-06-29).
- 2018 → 2026: No new permits, no inspections, no code-enforcement cases. The track functionally exists and is in long-term passive operation.
The pattern — three grading permits over six years to build a single track — is typical Sonoma practice when working in clay-loam soils on rolling terrain with the “Mostly Landslide” rating: drainage, BMPs, and slope stability all require engineered phasing. Adobe Associates is a known Santa Rosa civil/structural firm.
Sales & tax data
| Date | Event | Source |
|---|---|---|
| 2008-10-24 | Mosiman acquisition: $1,100,000 (Doc # 2008R096841) | Sonoma County Assessor (MBAP) |
| 2009-02-19 | First permit (driveway encroachment, Sheehan Construction as contractor) | Permit Sonoma |
| 2009-06-15 | Trust transfer (Doc # 2009R057779) — “Mosiman Steven T TR & Mosiman Helen C TR” | Sonoma County Assessor |
| (none since) | No subsequent transfer on record | — |
| Land value (assessed, 2025) | $1,291,631 |
| Improvement value (assessed, 2025) | $130,061 |
| Net taxable value (2025) | $1,421,692 |
| Tax Rate Area | 159003 (Unincorporated; ~1.075–1.10% effective rate) |
| Implied 2025 secured tax | ~$15,300–$15,600/year |
| Acquisition basis ($/acre) | $1.1M ÷ 51.15 ac = $21,506/acre at purchase (2008) |
| Holding period | 17.6 years |
Acquisition-to-current-assessed appreciation: $1.1M → $1.42M assessed (≈29% growth, consistent with Prop 13’s 2%/yr cap compounded over 17 years). Market appreciation is far higher — an off-market clearing today in the $2.5–3.0M range implies 2.3–2.7× the 2008 basis, or ~6%/yr unlevered return.
Deed image confirmation at https://crarecords.sonomacounty.ca.gov/Web/ ($1/page) would close out the chain.
Comparable sales
| Address | Date | Price | Acres | Structures | $/acre | Notes |
|---|---|---|---|---|---|---|
| 🆕 4201 Bloomfield Rd (in-laws — BERTY ENTERPRISE LLC) | 2025-12 | $2,485,000 | 46.15 | Existing SFD (VR-permitted under ZPE16-0070) + legalized barn | $53,847 | THE COMP. Directly adjacent, comparable size, fresh Dec 2025 transaction. APN 027-050-053. |
| 3545 Bloomfield Rd (5 Wells Vineyard — immediate NE neighbor) | ACTIVE listing, listed 2025-12-18 | $6,500,000 (cut from $10.5M) | 72 | 3,759 sf 2008 estate home + 32 ac planted Pinot/Chard vineyard | $90,278 | Wells / Kwon owners. MLS 325103677, listing agent David Carciere (Cru Land / Engel & Völkers St. Helena). 143+ DOM as of May 2026 |
| 12760 Green Valley Rd | Listed 2024-07-01 | $3,499,000 | 80 | Vacant ag land | $43,738 | Best raw-land $/ac comp in west Sebastopol |
| 9800-10000 Cherry Ridge Rd | 2023-02 | $4,525,000 | 28 | 22 ac planted Pinot Noir | $161,607 | Heavy vineyard premium |
| 2836 Bloomfield Rd | 2024-07-31 | $2,699,000 | 3.9 | Main house + party barn + new guest house | $691,795 | Small-lot residential estate (Press Democrat) |
| 6000 McFarlane Rd | Recent (off-market) | n/a published | 139 | Ranch home, mobile, century barn; DA20 zoning allowing 6-parcel subdivision | n/a | Large-tract benchmark |
| 4500 Bloomfield Rd | 2011-03-29 | $895,000 | 8.01 | 3,773 sf 5/4 home (1987) | $111,735 | Older, residential |
| 4050 Bloomfield Rd | 2017-12-21 | $1,099,000 | 5.23 | 3,500 sf 4/3 home (1977) | $210,134 | Residential |
The in-laws’ 4201 Bloomfield Dec 2025 acquisition at $53,847/acre is the single most relevant data point. Applied to 3845’s 51.15 acres: $2,754,329 straight-line. Adjust for:
- Mosiman parcel has 5 more acres of usable LEA land (+$270K at $53.8K/ac)
- 4201 has a working SFD + VR permit (a meaningful income asset); 3845 only has a small 1925 farmhouse on grandfathered systems → value differential of ~$300K–$500K in favor of 4201
- 3845 has the engineered motocross track — neutral-to-slight-discount for a typical buyer; meaningful premium for a MX buyer
Net: $2.5–2.9M is the bracket for a 4201-comparable transaction at 3845.
$/acre tier summary (west Sebastopol / Sebastopol Hills, 2023–2026)
- Raw vacant ag land, 50–100 ac, no significant home: $25K–$50K/acre (Green Valley benchmark $43,738/ac)
- Plantable but unplanted land in vineyard-suitable belt: $50K–$80K/acre (the “vineyard upside” premium)
- Land with developed vineyard + estate home: $90K–$160K/acre (5 Wells, Cherry Ridge)
Working valuation for 3845 Bloomfield
Two tracks:
- Track A — Raw ag land: 51 ac × $35–50K/ac = $1.78M–$2.55M
- Track B — Vineyard-development-potential (if soils support, similar to neighboring 5 Wells): 51 ac × $50–80K/ac = $2.55M–$4.10M
Adjustments:
- (Negative) LEA B6 160 zoning: new primary dwelling not permitted on this sub-160-ac parcel. The 1925 dwelling is legal nonconforming and may be maintained/replaced under that status, but a buyer cannot easily layer a new contemporary residence on top. This is the dominant value cap.
- (Negative) 5 Wells’ 38% list-price cut signals softening high-end vineyard demand into 2026.
- (Negative) The engineered moto-cross track is an irreplaceable amenity for a motocross household but treated as a $150K–$400K remediation cost by a typical vineyard / equestrian / residential buyer.
- (Positive) Scarcity — mid-size Bloomfield Rd parcels rarely trade.
- (Positive) Direct adjacency to a known vineyard validates the soils for Pinot Noir.
- (Positive) Twin Hills school district premium over Shoreline JUSD.
Estimated market value range (off-market, as-is): $2.5M–$3.0M Most likely clearing price if marketed today: ~$2.7M ($53K/ac, mirroring the in-laws’ Dec 2025 comp at the adjacent 4201 parcel)
For an off-market consolidation purchase by an adjacent / nearby Bloomfield Rd buyer, ~$2.6–2.8M is the right working assumption — recognizes the no-broker-fee savings (~5–6% = $150K) and the family’s emotional/sweat-equity investment in the property. Steve will not sell at a number that disrespects what they built; he knows the 4201 trade and will price accordingly.
The Mosiman family — who they are and how they got here
Steven Thomas Mosiman (age 68) and Helen C. Mosiman (~55) are a Sonoma County–based family. They live elsewhere in the Sebastopol area (~3 mi from the subject parcel; address on file in Steve’s CA SoS officer record for Sheehan Construction). Steven co-founded Sheehan Construction, Inc. with Tom Sheehan in November 1998 (“two guys and a big truck” — Steve had been running a large framing operation for someone else, Tom was running a successful layout business). The company is now ~$42M revenue, ~500 employees across Napa, Sebastopol, and Los Gatos operations. Steve is President; Tom is VP / Secretary / CFO / Registered Agent / CSLB RMO. Active CSLB general-building licenses 767115 + 809970.
The premise that “the owners live in LA” is incorrect: Steve’s officer address on the CA Secretary of State filing is a Sebastopol-area residence, and he physically runs a $42M Sonoma/Napa construction business. The family is locally rooted, not absentee.
The original briefing was right about the dirt-bike framing, though:
Michael Mosiman (younger son) — pro motocross / supercross
- Born July 16, 1999, in Sebastopol, CA — this means he grew up here, in school here, and almost certainly cut his teeth on the 3845 Bloomfield motocross track that his father permitted in 2009 (when Michael was 10).
- Pro debut 2017 with Rockstar Energy Husqvarna Factory Racing.
- Subsequent factory teams: Troy Lee Designs Red Bull GasGas (2021–2023), Monster Energy Star Racing Yamaha (2024–present).
- 2022 San Diego Supercross 250SX West winner; 3rd in 2022 250SX West championship.
- Multiple severe injuries — broken neck (2022), head injury (2023), neck fractures (2024); held a retirement party in 2024; cleared and returned to competition 2025; expected to race 2026 250SX West.
- Wikipedia, Pro Motocross profile, SupercrossLive bio, Instagram @_michaelmosiman.
Josh Mosiman (older son) — ex-pro, now MXA editor
- Older brother. Former pro Supercross/MX racer. 2018 National #71; pro debut Hangtown 2016.
- Now Assistant Editor and test rider at Motocross Action Magazine (MXA) — extremely public-facing, weekly columnist, regular author at motocrossactionmag.com.
- Married (2021 MXA “Flashback Friday” referenced wife as mechanic at Hangtown 450).
- Author page, Pro Motocross profile, Instagram @joshmosiman.
Family read
The most likely sequence:
- Steve & Helen, settled Sonoma County family, sons riding amateur MX from a young age (~mid-2000s).
- As the sons got serious (~2008), Steve uses his own construction company plus Adobe Associates engineering to acquire 51 acres + build out a permit-graded track. Steve’s day job — General Contractor — is exactly the skill set needed to navigate the engineering, grading, and county process; this is a project he could run as a side execution from his main business.
- Both sons turn pro (Josh 2016, Michael 2017). The track is functionally a finished training facility by 2015 (”@ 100%”).
- As the sons leave for the pro circuit (Michael to SoCal team bases at Husqvarna, GasGas, Yamaha), the track stays as a family asset. With Michael’s injury arc and near-retirement, plus Josh now in journalism (married, based in SoCal or remote), the day-to-day use likely has dropped significantly.
This squares the briefing’s “no one really uses it” framing with the actual ownership reality. The family uses the property (it’s their kids’ training ground), but the day-to-day intensity of use is way down from the 2010–2018 peak.
Risk / opportunity flags
- The motocross track is a feature, not a bug — if you’re motocross-oriented. It’s permit-graded by a credentialed civil engineer (Adobe Associates), the work is ”@ 100%” per the 2015 permit, and there’s no code-enforcement case on file. For a buyer who wants to keep riding (or wants the parcel for a non-MX use), the track is either an irreplaceable amenity or a ~$150–400K remediation/restoration cost (grade flat, reseed, address erosion controls).
- All three grading permits expired without being finaled. Material risk for any future expansion — a new buyer who wants to extend the track, add jumps, or modify drainage would need to start with a fresh GRD application from Permit Sonoma. Don’t assume the prior approvals can be revived.
- No Williamson Act contract. Same as 4707 Bloomfield — flexibility for a buyer to enter a contract or a conservation easement going forward, but no current tax break.
- Existing 1925 residence is small (804 sf) and on grandfathered septic. Material constraint on residential expansion. Any new SFD or expanded dwelling triggers fresh septic capacity review (Sonoma sizes by bedroom count) and likely a new well-yield test. The 1925 dwelling is functionally a teardown for any contemporary use case.
- Soils + landslide combo. LoE/LsE/SnD2 clay-loams on rolling slopes with “Mostly Landslide” rating means any new construction or grading requires engineered cut/fill, drainage, and BMP plans. Adobe Associates has institutional knowledge of this parcel.
- No AEX filings = no documented outbuildings. Anything on the parcel beyond the listed assessor improvements is either pre-Permit-Sonoma vintage, ≤120 sf ag-exempt, or unpermitted. Walk the site before pricing.
- Twin Hills / West Sonoma school districts are an asset. Notably better ratings than the Shoreline JUSD that the in-laws’ 4201 Bloomfield falls into. Relevant for any future residential development premium.
- OAK + SR overlays trigger review. OAK = Valley Oak Habitat (any removal/disturbance requires permit; common workaround is preserve in place and design around). SR = Scenic Resources (height/materials/visibility from Bloomfield Rd; not a hard prohibition but adds a review step).
- Owner profile makes them a sophisticated counter-party, not a forced seller. Steve runs a $42M construction company; he’s not under cash-flow pressure. With Michael’s racing career winding down, there may be a moment — but it’s a moment for the family to make their own choice, not for a buyer to extract.
- Local relationship liability. Steve’s business operates in the same Sonoma/Napa community. A poorly-handled approach (lowballing, indirect questioning of neighbors, etc.) will get back to him within weeks and torch the relationship for years.
Strategic notes for an off-market approach
What works
-
Neighbor-to-neighbor intro is the strongest opener. The in-laws (Berty Enterprise LLC at 4201 Bloomfield, ~0.5 mi west) or one of the directly-adjacent owners (Furlong directly north; Rudolph just west) are the natural channels. “I’m so-and-so’s son-in-law, we’re thinking about consolidating land along Bloomfield Rd, would you be open to a coffee” reads completely differently from a cold letter.
-
The right framing acknowledges what they built. Don’t open with “we’d like to buy your land” — open with “we admire what you’ve done with the property, and have an idea we’d like to discuss with you.” Make it about a conversation, not a transaction.
-
Be ready to talk about the track honestly. A motocross buyer would pay for it; a non-MX buyer would discount it. The Mosimans know both sides. Saying “we’d treat it as land, not as the track” is fine; saying “the track is a problem we’d have to remove” is offensive.
-
Sheehan Construction professional channel is fine for a formal letter or follow-up, but it’s the wrong opening move. A buyer who introduces himself by calling the office to ask for the boss is signaling a sales mindset, not a neighbor mindset.
What doesn’t
- Cold letters from a buyer they’ve never heard of, especially from a non-Sonoma address.
- Realtor-led approaches — Steve will recognize the cost loaded into the broker’s fee and treat any number as 5% low.
- Spreadsheet-led valuations (“comparable parcels are trading at X/acre”). He owns a 500-person construction company and can price the dirt himself.
- Implicit or explicit framing of the property as underused or wasted. The family chose to build it this way for their kids’ racing.
Contact channels — ranked
The Mosimans are willing sellers per your briefing. The following are ranked by likely effectiveness.
| Rank | Channel | Details |
|---|---|---|
| 1 | Hand-written letter to Steve’s residence | Steve’s residential address is filed publicly as his officer-address on the CA Secretary of State record for Sheehan Construction. Retrieve from CorporationWiki or bizfileonline.sos.ca.gov (search “Sheehan Construction”). A short letter introducing yourself as the son-in-law of the 4201 Bloomfield owner, mentioning you heard he might be open to a conversation about 3845, and asking for 15 minutes. Highest-probability single move. |
| 2 | Sheehan Construction Napa office | 477 Devlin Rd Ste 108, Napa, CA 94558 — phone (707) 603-2610. Steve takes business calls there. Open with: “Hi, this is [name], my in-laws own 4201 Bloomfield Rd — could I get 15 minutes with Steve on a neighbor-to-neighbor matter?” Don’t pitch on the phone; the goal is to get a meeting. |
| 3 | Sheehan Construction Sebastopol office | 1418 Gravenstein Hwy S, Sebastopol — phone (707) 823-8479. Closer to the property; Steve is often there. Tom Sheehan’s registered-agent address. |
| 4 | Letter to 3845 Bloomfield Rd directly | Steve & Helen check the mail at the property. Addressed to “Steve & Helen Mosiman, Trustees.” Lower-priority than the residence — slower turnaround. |
| 5 | Mutual-neighbor introduction | Your in-laws (Berty Enterprise at 4201, just acquired Dec 2025 — Steve probably noticed the sale and met the new neighbors at some point); Furlong at 3883 (just N, APN 025-100-004); Birse at 3858 (APN 025-100-024); LaForge (the vineyard owner at 3225, APN 025-100-043) — any of these is a possible warm introducer. Steve has been on Bloomfield Rd for 17 years; the neighbor network is dense. |
| 6 | Sheehan Construction LinkedIn | https://www.linkedin.com/company/sheehan-construction. Formal/slow channel — limited LI footprint (17 followers, 9 listed employees). Steve doesn’t appear to maintain a personal LI. |
| 7 | Josh Mosiman (son, MXA editor) | Public author page at https://motocrossactionmag.com/author/joshm/ and Instagram @joshmosiman. Useful only for a soft warm-up framed around the property’s training history — not for opening with a real-estate ask. |
Tactical framing for the opener
A draft letter to Steve might read something like:
Steve & Helen —
I’m [Name], married to [spouse], whose parents just acquired 4201 Bloomfield Rd last December. They’re starting to settle in and we’ve been spending time at the property. I noticed your place at 3845 in the course of getting to know the road, and word reached me through a roundabout channel that you might be open to a conversation about it.
No pitch here — just wanted to say we’d be honored to meet you, learn a bit about what you built there, and talk through whether there’s anything that makes sense for both sides. Happy to come to the Sheehan office whenever works, or buy you a coffee at the Wild Flour in Freestone if that’s easier.
Best, [Name] [phone] · [email]
That’s the right voice: neighbor-to-neighbor, no agenda asserted, no price math, names the path that got you here, leaves the next step in their hands.
Note: this page is published at 3845bloomfield.groeney.com. Specific personal details (Steve’s residential address, DOB) have been intentionally omitted from the public version; James has the full details in his local research notes. The CA Secretary of State filing for Sheehan Construction is the public record path if any reader of this page needs to look those up themselves.
What’s in source/
| File | Source |
|---|---|
permit-sonoma-parcel-report.md | Permit Sonoma zoning/parcel JSON for APN 025-100-006 |
permit-history.md | Permit Sonoma full permits API JSON for APN 025-100-006 (all 5 records) |
ownership.md | Owner / family background: CA SoS, CorporationWiki, BizProfile, BuildZoom (CSLB), Wikipedia, Motocross Action Magazine, Pro Motocross, Racer X |
loopnet-citydata.md | LoopNet + city-data.com tax-assessment data, plus corridor comparables |
sales-comps.md | Sales/listing/MLS context, comparable sales table, valuation tracks |
sonoma-gis-assessor.md | Authoritative Sonoma County GIS parcel + MBAP assessor data: sales chain, building inventory, assessed values, adjacent parcels in book 025-100 |
Known gaps / next steps
- Pull the 2008R096841 deed image — confirms prior owner (likely Tom Birse based on the city-data header) and any restrictions/easements recorded at the time. Sonoma Clerk-Recorder at https://crarecords.sonomacounty.ca.gov/Web/, ~$1/page.
- Record of Survey R/S 13-126, Book 762 Maps 11 — pull from same Recorder portal. Confirms surveyed boundary, easements, and any 2013 adjustments.
- Engineered grading plans (TIFF scans) — archived in Accela document IDs 4738926 and 4740155 in box 14528. Retrievable via
https://parcelsearch.permitsonoma.org/api/documents/{id}. Track footprint, cut/fill volumes, drainage design. - Aerial confirmation of the track — Sonoma County GIS ActiveMap (https://permitsonoma.org/gis/activemap) or Google Earth historical imagery (2010+). Should clearly show track footprint, structures, oak distribution, and pond/water-tank locations.
- Site visit / walk-the-land — current condition of track, the 1925 dwelling, the 1971 outbuildings (especially the 1,152 sf “other structure” — barn? shop? second outbuilding?), water sources, fencing.
- Confirm owner mailing address on the Mosiman Family Trust — interactive lookup at https://common1.mptsweb.com/mbap/SONOMA/Asr/AsrMain/025100006000 (requires browser).
- Track restoration cost estimate — if the intended use is non-motocross, a licensed grading contractor (or Adobe Associates themselves, who built it) can scope the remediation cost.
- Confirm 4201 Bloomfield Dec 2025 transaction — the in-laws’ acquisition date and price ($2,485,000) is the load-bearing comp. Cross-check the actual closing documents to confirm whether the price includes a contingency, a personal-property allocation, or other adjustments that would distort the per-acre comp for 3845.
- Steve’s personal cell / email — if the residence letter and office calls don’t get traction within 2–3 weeks, a licensed CA real-estate broker can pull cell/email from the MLS public-records side (standard professional tool, not aggregator data). Alternatively, the in-laws (now Steve’s literal neighbors as of Dec 2025) may already have his number.
Sources cited inline throughout. Pulled 2026-05-11 by Claude on behalf of James Groeneveld.