Duvall

Bonney Lake
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Snoqualmie

Why Choose Blue Lake?
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DADU Questions, Answered
How much does a DADU cost in Seattle?
Most detached ADUs in the Seattle–Bellevue area run $250,000–$450,000+, driven by size, site access, utility connections, and finishes. A garage conversion to a DADU can come in lower. Every Blue Lake DADU is quoted as a fixed price before construction starts.
What's the difference between an ADU and a DADU?
An ADU is built inside or attached to your existing home — a basement suite or an addition. A DADU (detached accessory dwelling unit) is a separate backyard structure such as a cottage or converted garage, with its own entrance, kitchen, and bathroom.
How long does a DADU take to build?
Expect 5–9 months of construction after permits, plus 2–4 months of design and permitting. A realistic full timeline is 9–14 months from first consultation to keys.
Do DADUs make good rental investments?
In the Seattle market a well-built DADU commonly rents long-term for $2,000–$3,200+ per month and adds appraised value to the property. Many of our clients build DADUs specifically as rental or multigenerational housing.
Serving Seattle, Bellevue, Kirkland, Redmond, and communities across King and Snohomish County. Licensed Washington general contractor #BLUELLC760C3.
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