Selling a duplex in Los Angeles, lived in or fully rented

Your duplex will sell either to someone who plans to move into one unit and let the other unit's rent help with the mortgage, or to an investor who wants both rents. Which of them you sell to, and whether a unit is empty on the day you close, decide what financing your buyer can use and which rent rules you both work under. They also move the price. If you live in one half now, the timing of your own move is part of that decision.

The buyer who moves in and the buyer who doesn't

Someone who plans to live in one unit is shopping for a home. Your tenant's rent is part of how they'll pay for it. They may be comparing your duplex with houses, condos and other small buildings at a similar price, and they'll walk through your unit the way anyone looks at a house.

The loans open to that buyer are built for homes of 2 to 4 units. FHA insures mortgages on one to four family dwellings with a minimum required investment of 3.5 percent. VA purchase loans cover 2 to 4 unit properties when the veteran lives in one of the units. A conventional loan written to Fannie Mae's guidelines, on a home the buyer will live in, lets the lender count part of the other unit's rent as the buyer's income. All three require the buyer to move in. And each one counts your tenant's rent its own way.

An investor wants both rents and will compare your duplex with other small rental buildings. A vacant unit isn't something they need. A rented one may even suit them better, as long as the rents, the leases and the rent control status hold up. Some investors are finishing a 1031 exchange. The IRS gives them 45 days from their own sale to identify replacement property in writing and at most 180 days to close on it. With your leases and records ready to hand over, you can sell to a buyer on that clock.

How a duplex is priced, next to a bigger building

A building of five units or more trades mostly on its income, because its lender sizes the loan from that income. A duplex falls on the home-loan side of that line. When the loan follows Fannie Mae's standards, the appraiser works on Fannie Mae's form for 2 to 4 unit homes, which backs up the market rent with comparable rentals. The borrower may be about to move in, too. So the sales that set your price are nearby sales of duplexes and other small buildings, read alongside what the rent would carry.

That changes what's worth doing before you list. Condition and layout count for more than they would in a forty-unit building, because your buyer may be choosing a home. The lot counts too. A duplex on a lot with room for more units can draw a buyer who is pricing what could be built there, and state ADU law and SB 9 decide how much room that is.

One cost that some larger buildings carry won't reach you. LADBS says the City's mandatory soft-story retrofit program doesn't apply to residential buildings with three or fewer units.

Should a unit be empty when you sell?

An empty unit lets you sell to owner-occupants as well as investors, because every owner-occupant loan requires the buyer to move in. FHA's handbook has the borrower occupy the home as a principal residence within 60 days of signing the mortgage. VA requires the veteran to live in one of the units. So before anything else, an owner-occupant needs to know which unit they would live in.

With both units rented in an RSO duplex, a buyer who wants to move in needs a tenant to leave. A tenant may go by choice, perhaps under a buyout agreement that follows LAHD's rules. If not, the buyer has to recover a unit through the RSO's owner occupancy process after closing.

That process has conditions. The buyer would need to own at least a quarter of the property, commit to living in the unit for two years in a row, file LAHD's Declaration of Intent to Evict before any notice goes to the tenant, and pay the tenant relocation money. Some tenants can't be moved out this way at all: anyone terminally ill, and anyone 62 or older or disabled who has lived there ten years or more. A unit recovered this way also keeps its controlled rent for the next tenant. An owner-occupant may decide that is more time, money and uncertainty than they want.

An empty unit matters to investors too, for a different reason. When a tenant leaves by choice or is evicted for not paying rent, the RSO lets the owner charge the next tenant a new rent. An investor may pay for that. In an RSO duplex, then, an empty unit can add more to the price than the rent it cost you while it sat empty. If a tenant gives notice while you're thinking about selling, decide which buyer you want before anyone signs a new lease on that unit.

Which rent and eviction rules cover your duplex

Where the duplex is and when its certificate of occupancy was issued decide which rules apply.

• In the City of Los Angeles, a duplex with a certificate of occupancy dated October 1, 1978 or earlier is under the RSO, and living in one unit doesn't take the other unit out of it. LAHD does offer an owner-occupied unit a temporary exemption from registration and SCEP fees, good for one year, and each owner on title can claim it for only one unit. For the year running July 1, 2026 to June 30, 2027, LAHD's allowable increase is 3 percent, and a tenancy can end only for a reason the RSO allows.
• A City of Los Angeles duplex certified after October 1, 1978 is outside the RSO. It is covered by the City's Just Cause Ordinance and by the state rent cap, Civil Code section 1947.12, unless an exemption fits, such as the state cap's exemption for housing first certified for occupancy within the previous 15 years. Both of those laws also exempt some owner-occupied two-unit properties.
• In unincorporated parts of the county, the County's own rent ordinance applies. In another city, check that city's rules. Where no stricter local rule applies, the state cap does.

If your duplex is newer and you live in one half, those owner-occupied exemptions may cover you. They last only while you stay. The state cap exempts a duplex in a single structure while the owner who lived there when the tenancy began goes on living there, and the exemption never applies when either unit is an ADU or a junior ADU. The City's Just Cause Ordinance exempts a two-unit property if an owner occupied the second unit for the whole tenancy. Move out or sell, and the words stop describing your building. Whether an exemption survives a sale is a question for the buyer's attorney. That attorney will ask for dates, so write down when you moved in and when each tenancy began.

How the IRS looks at a duplex you've lived in

The IRS treats the two halves of a duplex you've lived in differently. For the unit that was your home, IRS Topic 701 lets you exclude up to $250,000 of gain, or up to $500,000 on a joint return. To qualify, you must have owned the home and lived in it for at least 24 months of the 5 years before the sale. The rented unit is a separate dwelling, and IRS guidance limits the exclusion to the gain allocable to the part you lived in. Depreciation you took, or could have taken, on the rental side after May 6, 1997 can't be excluded. Topic 409 taxes that part of the gain, the unrecaptured section 1250 gain, at a maximum rate of 25 percent.

The tax on the rental side can be deferred. Its share of the sale can go into a 1031 exchange for other investment real estate, and Rev. Proc. 2005-14 explains how the exclusion and an exchange can both apply to one sale. Your basis, your depreciation history, the dates you lived there and California's own rules all move the numbers. A CPA should work out how the sale splits between the two units before you list. Shaya isn't a CPA or an attorney. He can tell you what the duplex should sell for, and a CPA can tell you how much of that you keep.

Room for more units on the lot

HCD's March 2026 ADU handbook says state law makes cities allow ADUs on a lot that already holds a multifamily dwelling. Some can be converted from space in the building that isn't used for living. Detached ones can be added too, up to the number of units already on the lot. A junior ADU isn't allowed in a duplex. Ask the City how those rules apply to your duplex before you or a buyer count on a number.

SB 9 applies only in single-family zones. It also can't be used for a project that would demolish or alter rent-controlled housing, or housing a tenant has occupied in the last three years. A pre-1978 duplex in the City of Los Angeles is under the RSO, so an SB 9 project that would demolish or alter one is out. What either law could add to your lot depends first on its zone, which ZIMAS will show you.

What to do, in order

1. Pin down the facts. Find the certificate of occupancy date, look the address up on LAHD's RSO property search, and check the zoning and permit history on the City's ZIMAS map. Make a note of any work done without permits.
2. Decide which buyer you're selling to. That tells you whether to keep a unit empty and when to tell your tenant about the sale.
3. See a CPA before you list. The split between the exclusion and the rental side, and any exchange, are easier to plan than to repair.
4. Pull the rental records together. Leases, the rent history, deposits, the RSO registration if the duplex has one, and copies of any notices you've served.
5. Get the empty unit ready, if there is one. An owner-occupant will judge it as the place they are going to live.
6. Price it against the right sales. Use recent nearby sales of duplexes and small buildings, adjusted for rent control status, condition and whether a unit was delivered empty.
7. Market to both kinds of buyer. Then weigh each offer by its financing, since a financed buyer's appraisal has to support the price.
8. Open escrow and close. Hand over the leases and records, and work out showings and inspections with your tenant.

Shaya can walk through the duplex with you, tell you which buyers it suits as it stands, and show you what changes if a unit is empty at closing.

What comes out of the price

What you walk away with is the price less the loan payoff, the commission, escrow and title charges, transfer taxes and any income tax on the gain. Inside City of Los Angeles limits there is also Measure ULA. It is charged on the full price once the price passes its first threshold. The Office of Finance puts that threshold at consideration above $5,400,000 for anything transferred on or after July 1, 2026. If your price could come near it, check the current figure, and check it again after each July 1, when the thresholds adjust.