Multifamily and Duplex Properties for Sale in Cobb: Zoning and Rent Rules

What multifamily in Cobb looks like

Cobb has almost no apartment buildings. On Cobb Mountain, income property usually means a house with a second unit or ADU, an occasional duplex, cabins on a resort or retreat parcel, or mobile homes on rural land. The Cobb Mountain Area Plan says about a dozen subdivided clusters hold nearly 90% of the area’s homes. They include Adams Springs, Cobb Estates, Cobb Valley, Loch Lomond, Pine Grove and Whispering Pines. Many were created in the 1950s and 1960s, before the county’s 1971 subdivision ordinance, with substandard lots and infrastructure. Outlying rural parcels are usually five acres or larger. The plan names moderate- and low-income housing and multifamily and mobile home housing as community needs. For financing, see financing 2-4 unit properties and apartment building loans.

Where the zoning allows it

Cobb is unincorporated and follows the Lake County zoning ordinance. Because most lots use wells and septic, the "well and septic" lot minimum governs:

ADUs and second units. County Article 27 allows one granny unit or one second unit per lot. A granny unit can be up to 720 square feet on lots under 40,000 square feet, or 1,008 square feet on larger lots, with one or two parking spaces. A guest house without a kitchen cannot be rented separately. State ADU law may expand these limits, so confirm with the county. In practice, septic capacity is usually the limit. See our ADU investment guide.

SB 9. SB 9 reaches unincorporated land only in qualifying urban areas, and it excludes some very high fire hazard sites unless mitigation standards are met. Much of Cobb is rated very high wildland fire hazard, so assume SB 9 is unlikely until the county confirms otherwise. See our SB 9 guide.

Rent rules: state law only

The Attorney General’s rent cap page lists no local rent control in Lake County. Covered units follow the "All Other Counties" row: 7.7% from August 1, 2025, and 8.6% from August 1, 2026 through July 31, 2027. Many single-family homes owned by individuals are exempt with proper lease notice, but a house with an ADU on one lot may be treated differently. See our AB 1482 guide and just cause eviction guide.

Cobb rental property rules

• Short-term rentals. Cabins draw vacation renters. The county formed a committee in July 2026 to help draft short-term rental rules for unincorporated areas. Stays of 30 days or less already owe the 9% TOT.
• Mobile home and RV parks. New parks need a major use permit, 5 acres and no more than 10 spaces per acre under Article 43.
• Resort cabins. The plan lists resorts at Howard Springs, Loch Lomond, Pine Grove, Salminas and Whispering Pines. Cabins there may be permitted as lodging, not apartments. In CR, housing is limited to caretaker or employee quarters with a minor permit.
• No county rental registry appears in the code we reviewed.

Water, septic, fire and rebuild issues

• Water. The State Water Board reports that the Cobb Area County Water District was formed in 2018 from seven systems damaged by the 2015 Valley Fire. It now serves about 1,000 connections. The fire cost the district 38% of its customers, and Starview lost 87%. The State identified $21 million in needed upgrades and classified the area as severely disadvantaged. Ask about connection fees and capacity for an added unit.
• Septic. The plan calls for monitoring older septic systems where density tops one unit per acre and for tracking failures in the Cobb area. Get a septic inspection and confirm capacity for every bedroom you plan to rent.
• Wells. The plan encourages voluntary heavy metal testing of new wells in areas with serpentine geology.
• Fire. South Lake County Fire Protection District serves the Cobb area from volunteer stations, according to the plan. Lake LAFCo’s 2025 review lists its special tax at $236 plus CPI. Budget for insurance, defensible space and fire-safe construction.
• Geothermal. Cobb lies within the Geysers geothermal resource area, and the plan notes hydrogen sulfide odor complaints north of the mountain.

Underwriting a Cobb income property purchase

1. Confirm the county district, the lot area and whether each unit is legally permitted, such as a granny unit or second unit.
2. Identify the water source and get septic capacity confirmed for all bedrooms.
3. Classify units under AB 1482 and model increases at or below 8.6%.
4. Treat vacation-rental income as uncertain until the county ordinance is adopted, and confirm TOT registration.
5. Collect leases and statements, and get estoppel certificates.
6. Rebuild expenses with reassessed taxes, insurance, the fire special tax and water district charges in our rental property analysis.

Questions people ask

Sources & notes

1. Cobb Mountain Area Plan (preliminary draft, 1989)
2. State Water Resources Control Board, Cobb consolidation story
3. Lake County Zoning Ordinance: Art. 7 RL, Art. 8 RR, Art. 10 R1, Art. 11 R2, Art. 12 R3, Art. 27, Art. 43
4. Lake LAFCo Fire Protection Districts MSR (2025)
5. California Attorney General, Rent Caps
6. Lake County STR committee news and TOT Ordinance

Note: The area plan is a 1989 draft that predates the Valley Fire. Mapped zoning, fire hazard severity zones and SB 9 eligibility were not verified on county or state maps. The R1, RR and RL articles were not reviewed in detail.

General information, not legal or tax advice. Last reviewed October 2026 by Matthew Martinez.

Related: Cobb real estate guide · Commercial real estate in Cobb · Multifamily investing guide · Investor services