Accessory dwelling unit rental — Costa Mesa, CA

Last updated: September 24, 2026

What affects the price

Building an ADU involves several moving parts that shape your total investment. The final figure depends heavily on whether you choose a prefab unit or a custom build from the ground up. Site conditions are another major factor; if your property requires extensive grading, utility trenching, or foundation work, costs will climb. You also have to consider your choice of finishes, like high-end appliances or custom cabinetry. Navigating local permit fees and impact assessments also adds to the total.

About this service

This involves setting up a secondary unit on your property specifically to lease to tenants. You need this service if you are interested in generating monthly income while maintaining your property ownership. We focus on layouts that maximize tenant appeal and ensure privacy for both your main home and the rental unit.

Frequently asked in Costa Mesa

Also serving nearby: Santa Ana · Huntington Beach · Westminster · Irvine · Garden Grove

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More on this: HUD ADU resources — ADU policy and financing research.

Service area details

Serving all of Costa Mesa — population 108,354; about 6,855 residents per square mile across 15.8 sq mi. ZIP codes covered include 92626, 92627, 92628.

Neighborhoods served in Costa Mesa: South Coast Metro, Mesa Verde, The Mesa, Westside Costa Mesa, Eastside Costa Mesa, College Park — and every surrounding area.