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
A prefab ADU is built in a factory and then transported to your property for final assembly. You might choose this if you want a faster construction timeline and less mess in your backyard compared to a traditional build. Because the structure is made off-site, it often helps with site control and weather-related delays. Exact pricing confirmed free on the call.
Frequently asked in Quincy
What are the financing options for an accessory dwelling unit in Quincy?
How do I get an accessory dwelling unit permit in Quincy?
What are the benefits of a backyard accessory dwelling unit in Quincy?
What are the rules for accessory dwelling unit rental in Quincy?
What ADU services are available in Quincy?
What is the typical accessory dwelling unit cost in Quincy?
How can I find an affordable accessory dwelling unit in Quincy?
Also serving nearby: Boston · Cambridge · Newton · Brockton · Lynn
More on this: HUD ADU resources — ADU policy and financing research.
Service area details
Serving all of Quincy — population 101,597; about 6,130 residents per square mile across 16.6 sq mi. ZIP codes covered include 02169, 02170, 02171, 02269.
Neighborhoods served in Quincy: Germantown, West Quincy, North Quincy, South Quincy, Wollaston, Merrymount — and every surrounding area.
Areas we serve
Browse by state, then city.
California (3)
All of California · Costa Mesa · Jurupa Valley · Santa Maria
