Home / Investors / Sell a Multifamily Property

Sell an Apartment Building or Multifamily Property in the North Bay

By Matthew Martinez, Founder, CEO & Managing Broker, Diamond Real Estate Group. California DRE #01869679.

To sell an apartment building well, price it on its income, document that income before you list, and plan around the tenants who live there. Buyers of multifamily property pay for net operating income, rent upside and condition, and they test each of those in escrow. A seller who arrives with a clean rent roll, a trailing 12-month operating statement and signed tenant documents gives buyers fewer reasons to retrade the price.

Diamond Real Estate Group lists duplexes, triplexes, fourplexes and larger apartment buildings in Sonoma, Napa and Marin counties, San Francisco and the East Bay and South Bay investor markets, including Oakland, Berkeley and San Jose. This page explains how we approach a multifamily sale, what you’ll be asked for, and which California rules shape the process. For the tax side of selling a rental, see our separate guide linked below.

How a multifamily sale differs from selling a house

A house sells mostly on comparable sales and how it shows. An income property sells on what it earns, what a buyer believes it could earn, and how much risk sits between the two.

Question	2 to 4 units	5 or more units
Typical buyers	Owner-occupants who live in one unit, plus small investors	Investors, often with a 1031 exchange to complete
Typical financing	Residential loans are available, including for owner-occupants	Commercial or apartment loans underwritten on the property’s income
Main pricing evidence	Comparable sales, with rent income as a cross-check	Net operating income, cap rate and price per unit
Showings	Often include occupied units, on proper notice	Often limited to a sample of units after an accepted offer

The split shapes everything else. A fourplex can draw a buyer who will move in, which widens the pool and can support a higher price than the income alone would. Our guide to financing 2 to 4 unit properties explains what those buyers can borrow, and our multifamily investing hub covers the larger-building market by county.

Pricing on income: NOI, cap rate and GRM

We build a price from three angles and then test it against the buyer pool most likely to pay it.

Net operating income (NOI): collected rent and other income, minus operating expenses such as taxes, insurance, utilities paid by the owner, repairs and management. Debt payments are not an operating expense. Our NOI guide walks through the line items buyers will question.
Capitalization rate: NOI divided by price. A buyer’s cap rate reflects interest rates, the building’s age and condition, and the market. See how cap rates work.
Gross rent multiplier (GRM): price divided by gross annual rent. It is a quick screen for small buildings where expense records are thin.
Comparable sales: price per unit and per square foot from recent sales of similar buildings, which matter most for 2 to 4 units.

Buyers will rebuild your NOI with their own assumptions, often a fresh property tax figure at their purchase price and a management fee even if you self-manage. We price with those adjustments in mind, so the asking price is more likely to hold up in underwriting. Owners who want a starting figure can request a property valuation.

The documents buyers and lenders will ask for

Multifamily escrows can stall over missing paperwork as easily as over inspections. Assembling these before listing gives you control of the story the numbers tell:

Rent roll: unit, tenant, move-in date, current rent, last increase date, deposit held, and any concessions or arrears.
Trailing 12-month operating statement (T-12): month-by-month income and expenses, ideally tied to bank statements or tax returns.
Leases and addenda: every current lease, parking and storage agreements, and any written rent or pet agreements.
Security deposit ledger: the amount held for each unit, because deposits move to the buyer or back to the tenants at closing.
Service contracts and utility bills: laundry, trash, landscaping, pest control and the last 12 months of owner-paid utilities.
Permits and building records: permits for past work, any code notices, and status of state or local inspection programs such as SB 721 balcony inspections or seismic retrofit ordinances.

Expect the buyer to request tenant estoppel certificates, in which each tenant confirms rent, deposit and lease terms. Our page on estoppel certificates explains what California tenants can and can’t be required to sign.

Rent rules a buyer will check

Rent regulation shapes what a buyer will pay, because it limits how fast rents can rise. Before listing, we sort each unit into its regulatory status:

State rent cap (AB 1482): Civil Code 1947.12 limits increases over any 12 months to 5% plus the change in the cost of living, or 10%, whichever is lower. Exemptions include housing that received its certificate of occupancy within the previous 15 years and a duplex where the owner occupies one unit. The section is set to repeal on January 1, 2030.
Just cause (AB 1482): after a tenant has lawfully occupied for 12 months, Civil Code 1946.2 generally requires just cause to terminate, stated in the notice. A sale is not on either the at-fault or no-fault list. See our AB 1482 guide for landlords.
Local ordinances: cities such as Oakland and Berkeley have their own rent and eviction rules, with registration and fees. Our East Bay rent stabilization guide summarizes them city by city.
Increase history: buyers compare the rent roll to the allowed increases, so keep notices and dates for each unit.

Disclose what you know about each unit’s status rather than leaving the buyer to assume. A unit that is below market but capped is worth less to a buyer than a unit that can be brought to market at turnover.

Showing occupied units: notice rules

Tenants keep their rights during a sale. Civil Code 1954 lets a landlord enter to show a unit to prospective purchasers, but only with reasonable notice and during normal business hours unless the tenant agrees otherwise.

Written notice: 24 hours’ written notice is presumed reasonable under the statute.
Oral notice for sale showings: notice may be given orally if the tenant was told in writing, within 120 days before, that the property is for sale and that the landlord or agent may contact them orally to arrange showings. The oral notice must still give the date, approximate time and purpose.
Proof of entry: after a showing arranged by oral notice, the landlord or agent leaves written evidence of the entry inside the unit.

Our recommendation is a limited showing schedule: exterior and common areas first, then a vacant or sample unit, with full unit walks reserved for the buyer under contract. The aim is to limit entries into tenants’ homes and keep their goodwill for the estoppel stage. Houses and condos with tenants follow the same entry rules.

Marketing to owner-occupants and investors

We market small buildings to both buyer groups at once, with income figures for investors and unit-level detail for owner-occupants. Larger buildings get an offering package with the rent roll, T-12 summary, unit mix and rent comparisons, released to qualified buyers.

Diamond also reaches likely buyers through its own client database and targeted off-market campaigns. Whether a listing can be marketed that way, and for how long before it goes to the MLS, depends on MLS rules and NAR’s Clear Cooperation Policy, which we’ll explain before you choose. We can’t offer you other brokerages’ private listings as replacement properties, but we can search the market for you.

Taxes, 1031 timing and closing logistics

Selling a rental usually triggers capital gains and depreciation recapture, and California withholds on many sales at closing unless an exemption applies. Our guide to selling a rental property in California covers the tax layers and the Form 593 withholding.

If you plan to buy again, a 1031 exchange lets you defer gain by acquiring like-kind real property. Federal law gives you 45 days after the transfer to identify replacement property and 180 days, or the due date of your return if earlier, to receive it. The exchange must be set up with a qualified intermediary before closing, so tell us early.

Other closing items to plan for:

Security deposits: under Civil Code 1950.5, the seller either transfers each deposit, less lawful deductions, to the buyer and notifies the tenant with the buyer’s contact details, or returns it to the tenant with an accounting. Before the sale, the seller gives the buyer a written statement of the deposits and the option chosen.
Prorations: escrow normally credits the buyer for rent the seller collected covering days after closing.
Transfer tax: county and city rates vary, and custom on who pays varies by market; see California transfer tax.
Several buildings at once: the order of sales and exchanges matters for taxes and replacement timing; see our portfolio disposition page.

Diamond may refer you to partners we work with; you’re free to choose any provider. That includes intermediaries, property managers and contractors.

This is general information, not legal or tax advice; talk to a California landlord-tenant or real estate attorney and a tax adviser before you list.

How a Diamond multifamily listing runs, step by step

Review: we look at the rent roll, T-12, leases and building records, and identify which units are rent-capped or locally regulated.
Pricing: we prepare an income and comparable-sales analysis and agree on a pricing strategy with you.
Preparation: we plan repairs worth doing, written tenant notices and a showing schedule.
Marketing: we release the offering package and MLS listing and contact likely buyers.
Offers: we compare price, financing, contingency periods and 1031 timing, not just the headline number.
Escrow: we coordinate estoppels, unit inspections, lender appraisal and deposit transfers through closing.

Questions people ask

How do you value an apartment building?

Mostly on income. Buyers apply a cap rate to net operating income and compare price per unit with recent sales. For 2 to 4 units, comparable sales carry more weight because owner-occupants are in the market.

Can I sell a duplex with tenants in it?

Yes. Leases and tenant protections stay in place when the property sells, and the buyer takes the property subject to them. You must give proper notice under Civil Code 1954 before showing occupied units.

Do I have to tell buyers whether units are rent-controlled?

Buyers will ask, and you should disclose what you know about each unit’s status under AB 1482 and any local ordinance. A rent roll with increase dates helps the buyer confirm it.

What happens to tenants’ security deposits when I sell?

Under Civil Code 1950.5, you either transfer the deposits to the buyer and notify the tenants, or return the deposits to the tenants. The transfer is usually handled as a credit in escrow.

Should I empty units before selling?

Not usually. Under AB 1482, a planned sale is not itself a just cause to end a covered tenancy, and local ordinances can add limits. Vacant units can help a buyer who wants to move in or renovate, so talk to a landlord-tenant attorney before giving any notice.

Can I do a 1031 exchange when I sell?

Yes, if you held the building for investment and buy like-kind real property. Set up the exchange with a qualified intermediary before closing; the 45-day and 180-day periods start at the transfer.

Can you sell my building off-market?

Diamond can contact likely buyers through its own database and targeted campaigns. MLS rules, including NAR’s Clear Cooperation Policy, limit public marketing outside the MLS, so we’ll go over the options before you decide.

If you own a duplex, fourplex or apartment building in Sonoma, Napa, Marin or another county we serve, we can review the numbers with you and outline a sale plan. Start on our investor services page or reach us through contact us.

Sources & notes

Last reviewed October 2026 by Matthew Martinez.