Is this home a duplex or a house with an ADU? Why it matters for the loan

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Illustrative image of main house and separate backyard cottage with individual entrances — Illustrative image. Not a photo of the people discussed.

I flagged a file where the borrower's description of the property did not match the county and agent information about its unit count.

That needed to be sorted out before we relied on the pricing.

We need to finance the property it actually is, not the description that produces the nicest quote.

Start with the property facts

A separate entrance or a second kitchen does not settle the question by itself. Neither does the listing description.

A home with an accessory dwelling unit, or ADU, is not automatically a duplex for mortgage purposes. The property records, legal use, appraisal and lender review need to support the classification.

I would gather the available information and ask what is still unresolved. A permit, a title description and an appraisal can answer different questions.

Find out what changes in the loan

Once the classification is supported, ask what it means for:

The loan programs available.
The down payment or equity needed.
The appraisal review.
Whether rental income can be used.
The pricing and payment.

If the original quote assumed one unit and the review supports two, we need an updated comparison.

Do this before building a plan around the rent

An extra space may be useful to your family or attractive to a tenant. That does not automatically mean all its expected rent or value can be used in the mortgage calculation.

I would rather resolve the unit question early than change the financing after you have planned around it.

Bring the property information you have. We can identify what the appraiser and lender need before treating a quote as a workable plan.

This example is based on a real mortgage discussion with identifying information removed. Any numbers are illustrative and are not current loan terms or a commitment to lend. Loan programs, rates, property values and borrower qualification vary.

Sources and further reading