Buying a Claremont Home That Already Has an ADU

The listing shows a second kitchen. Or a studio over the garage, a converted back building, a unit with its own entrance and its own address on the mailbox. Sometimes the description is confident and sometimes it is careful: guest quarters, bonus space, workshop with plumbing.

An existing accessory dwelling unit can be a genuinely good thing to buy. It can house family, it can produce income, it can hold its own value. It also brings four questions with it that a single-unit purchase does not, and each of them is answerable before you remove contingencies.

Question one: is it legal

Start here, because everything else depends on it.

Ask for the permits. Request the permit history from the city building division for the address and look for the unit specifically: issued permits, final inspection, and whether any permit sits open. The method is the same one you would use for any addition, set out in checking permit history before you buy in Claremont.

Understand the range of possibilities. The unit may be fully permitted and finaled. It may have been permitted under an earlier framework. It may be unpermitted. It may have been built under one of the pathways that have existed for legalizing certain existing units, and if so there should be a record.

State and local rules in this area have changed a great deal in recent years and they continue to change, so ask the city what applies today rather than relying on what was true when the structure was built. If the unit is not permitted, ask the city directly what a legalization path would require, before you decide what the property is worth to you.

Question two: what does it do to your loan and appraisal

Tell your lender there is a second unit at the start of escrow. Not the week before closing.

Loan programs treat accessory units differently, and treatment can depend on whether the unit is permitted. If part of your plan is to have rental income considered in qualifying, that is a specific question with specific documentation requirements, and the answer belongs to your lender rather than to an assumption.

The appraisal is its own matter. An appraiser decides how to treat the unit, and an unpermitted structure may be handled very differently from a permitted one. That treatment can affect value and therefore the loan.

Question three: who is in it right now

If the unit is occupied, you are buying a property with a tenancy attached and that changes your purchase substantially. A sale does not end a lease, and the terms, deposits and possession questions all need settling in writing before you commit. The full sequence is in buying a tenant-occupied home in Claremont.

If the unit is vacant, confirm in writing that it will be delivered vacant and that nothing is left behind.

If a family member is living there informally, ask directly what the arrangement is and what will happen at closing. Informal is exactly the kind of arrangement that becomes a surprise.

Question four: how does it actually function

Inspect it as a separate building, not as a bonus.

UTILITIES. Is it separately metered for electric, gas and water, or does it share with the main house? Shared metering is workable but it shapes how you can charge for anything and how you settle bills.

SYSTEMS. Its own water heater, heating and cooling, panel, and drainage. Age and condition of each.

PLUMBING AND SEWER. How it connects to the main line, and whether that line has been inspected. A camera inspection is worth it here.

PARKING AND ACCESS. Where does a second household park, and how do they reach the unit? This is a daily-life question that people only discover after moving in.

PRIVACY. Sightlines, windows, noise and outdoor space between the two dwellings. If you intend to live in the main house, this is the thing you will actually notice every day.

Ask what the seller has actually been doing with it

Facts beat description here. Ask in writing whether the unit has been rented, and if so on what terms and for how long. Ask whether it has ever been used for short-term stays, because that carries its own local rules. Ask whether utilities were shared and how that was handled between households. Ask whether anything about the unit has been the subject of a complaint, a notice or a dispute with the city or a neighbor. None of those questions is aggressive; they are the same questions you would want answered if you were on the other side of the table, and the answers tell you what you are inheriting.

Insurance, taxes and the boring parts

Tell your insurance carrier there is a second unit and say plainly whether it will be rented. Coverage for a property with a rental unit is not the same product as coverage for a single-family home, and an unpermitted structure raises its own questions.

Ask a tax professional about the consequences of renting part of your property, because those belong to a qualified advisor rather than to a real estate article. And if you plan to rent it, ask the city what local requirements apply, including anything about registration, inspection or the type of tenancy permitted.

The checklist

Pull the permits. Ask the city what legalization would require if the unit is not permitted. Tell your lender at the start. Understand how the appraiser will treat it. Settle possession in writing. Inspect it as its own building including the sewer connection. Confirm utilities and parking. Quote insurance with the true use disclosed. Ask a tax professional about the income side.

Do all of that and an accessory unit is one of the more useful things a property can come with. Skip it and you have bought a structure whose legal status, insurability and occupancy you learn about later.

More buyer guidance is in the buying a home hub.

Anthony Grynchal has been licensed in California since November 2009.