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

What multifamily in Clearlake looks like

Clearlake’s rental stock is mostly small: duplexes and fourplexes on older lots, cottage courts and motels, manufactured homes and mobile home parks, and a few apartment complexes near Lakeshore Drive and Olympic Drive. Much of the city was platted long before modern standards, and many lots lack streets, sewer or water. The city created a separate Avenue combining district for these "paper subdivisions." Two things set Clearlake apart from the rest of Lake County. It has its own rental registration and inspection ordinance, and it adopted a new zoning chapter in 2025. For financing, see financing 2-4 unit properties and apartment building loans.

Where the zoning allows it

Ordinance 271-2025 replaced the city’s district list (Section 18-2). The use table in Section 18-18 lists "multifamily/multi-dwellings (duplexes, triplexes, etc.)" as follows:

The table also sets minimum unit sizes of 450 square feet for duplex, townhome and multiplex units. Primary units of 400 to 749 square feet ("micro" dwellings) need an administrative permit in residential zones. Mobile homes more than 10 years old cannot be placed. Manufactured home parks need a conditional use permit in RR, LDR, MDR, HDR and MUX.

ADUs. Accessory and junior accessory dwelling units are allowed in RR, LDR, MDR, HDR, DC, MUX and O, and need a conditional use permit in GC and IN. Standards are in Section 18-19.320. See our ADU investment guide.

SB 9. Clearlake is an incorporated city, so SB 9 duplex and lot-split rules can apply to qualifying single-family parcels. Lots without sewer, in flood zones or in high fire areas may face limits. The city sections we reviewed do not set SB 9 standards, so confirm with planning. See our SB 9 lot split guide.

Rent rules: state law only

The Attorney General’s rent cap page does not list a local rent control law in Clearlake. Lake County falls in the "All Other Counties" row: 7.7% for increases from August 1, 2025, and 8.6% from August 1, 2026 through July 31, 2027. State just cause and relocation rules apply to covered tenancies. See our AB 1482 guide and just cause eviction guide.

Clearlake rental property rules

Registration and inspection. Article 9-4 (Ord. 102-01, amended by Ord. 279-2025) applies to apartments, rental houses, motels, hotels and lodging houses, along with their common areas. A unit counts as rental if it is offered for even one day a year. Owner-occupied units and owner-only vacation homes are exempt. Key points:

• Owners register each parcel and pay an annual fee before a unit is first offered for rent, or within 30 days of a certificate of occupancy for new construction.
• An initial inspection follows registration, and the city may require annual inspections. It gives at least 10 days’ notice.
• A unit needs an inspection certificate to be lawfully occupied. Violations generally must be corrected within 30 days of notice, and no certificate issues until they are.
• After a clean initial inspection and 12 months without substantiated violations, owners may self-certify for three years.
• On a sale, the seller notifies Community Development before closing, or the buyer notifies within 60 days. If neither does, the inspection certificate ends automatically.
• Anyone offering more than five units for rent needs a business license.

Vacation rentals. Short-term rentals need a city permit under Section 18-19.280. The permit belongs to the owner and ends when the property is sold. ADUs and JADUs cannot be used as vacation rentals. Overnight guests are capped at two per bedroom plus two, with a maximum of 12, and a lower cap applies on limited septic systems. A manager must be available 24 hours a day within 30 miles. The 9% transient occupancy tax applies. Do not underwrite a buyer’s short-term income on the seller’s permit.

Sewer, older buildings and site constraints

• Sewer timing. In the Southeast Regional Wastewater Treatment Plant service area, Section 9-3 voids a building permit if the foundation is not done within 60 days, and the sewer connection permit is forfeited.
• Older masonry. Chapter IX has an article on potentially hazardous unreinforced masonry buildings (9-2). Ask whether any older commercial or mixed-use building is on that list, and consider a seismic retrofit review for older wood-frame stock.
• Balconies. Buildings of three or more units with elevated decks or stairs need SB 721 inspections.
• Floodplain. Lakefront parcels may fall under Chapter XVII floodplain management.
• Paper lots. In the Avenue combining district (Section 18-14), access and fire protection standards come before density.

Underwriting a Clearlake multifamily purchase

1. Confirm the 2025 zone, any combining district, and that the unit count is legal at the zone’s density.
2. Get the parcel’s Article 9-4 registration, inspection certificates and any open correction notices, and plan the 60-day change-of-ownership notice.
3. Classify units under AB 1482 and model increases at or below 8.6%.
4. For any motel or cottage court used as housing, confirm the permitted use and its tax and registration history.
5. Collect leases, the rent roll and two years of statements, and get estoppel certificates.
6. Rebuild expenses with reassessed taxes, the registration fee, the city transfer tax and sewer charges in our rental property analysis.

Questions people ask

Sources & notes

1. Clearlake §18-2, Zones Established (Ord. 271-2025)
2. Clearlake §18-18 Use Regulations
3. Clearlake district standards: §18-5 MDR, §18-6 HDR, §18-7 MUX, §18-8 DC
4. Clearlake Article 9-4 Rental Housing Registration and Inspection and §9-4.8
5. Clearlake §9-3 Southeast wastewater permits
6. Clearlake §18-19.280 Vacation Rentals, §18-14 Avenue district, §3-3.3 TOT
7. California Attorney General, Rent Caps

Note: The registration fee amount and the list of unreinforced masonry buildings were not verified.

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

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