ADU Rental Income and Mortgage Qualification

Confirm how the property is classified

Collect permit and zoning information and let the appraiser identify the property’s legal use and unit configuration. A separate entrance or an online rental listing does not by itself establish an eligible second unit.

Disclose kitchen, bathroom, access and utility arrangements. The appraiser’s classification affects both the property program and the rental-income documentation.

Document the rent instead of assuming it counts

Provide an executed lease when available, rental history and appraisal-supported market rent. The lender must confirm whether and how the selected program accepts income from the accessory unit.

Do not automatically add an ADU’s projected rent to the primary dwelling’s rent. A borrower-income program and a DSCR program may apply different eligibility and calculation rules.

Match the proposed use to the loan

For a primary residence with a rented accessory unit, review owner-occupied financing. Standard DSCR is for investment occupancy. If the ADU will be a short-term rental, local permission, property eligibility and STR documentation must all be reviewed.

A conversion or unpermitted unit can affect collateral acceptance. Explain planned construction separately from the property’s current condition; permanent mortgage eligibility should not be assumed to finance unfinished work.

Bring an ADU review package

Complete property information lets the team assess the right income path before a loan estimate becomes a purchase assumption.

• Permits, zoning information and the appraised unit configuration.
• Lease, rental history or proposed rent and its supporting market evidence.
• Floor plan, separate access and utility details.
• Your occupancy plan and the property’s current condition.