4400 88th Ave SE, Mercer Island, WA 98040

Commercial · Mercer Island · Seattle-Bellevue metro, WA

Imagery suggests: single-story service building. AI estimate from public imagery. In recent public imagery (2026-06), the building appears well maintained. AI estimate from public imagery; may be outdated.

One of 23 reachable commercial buildings in Mercer Island. Larger than 17% of commercial buildings in Mercer Island (median 41,832 SF), derived from assessor records.

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Building size
14,650 SF, King County Assessor
Lot size
36,000 SF, King County Assessor
Year built
1990, King County Assessor
Stories
2, King County Assessor
Predominant use
Mercer Island Library, King County Assessor
Assessed value
$0, per the King County Assessor (not a market appraisal)
Lot coverage
41%, derived from assessor records
Vintage
1990s vintage
Zoning
R-9.6, King County
County use code
Governmental Service
Construction (observed)
masonry, AI estimate from public imagery
Parking (observed)
surface lot, AI estimate from public imagery

Nearby comparable buildings

Same building type, by distance. Assessor facts only; not an opinion of value.

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Sale history and market context

Source: King County recorded sales extract; buyer and seller shown only when a company or organization. Individual names are withheld.

Land, site, and value history

Permit history

Source: King County permit records (newest first).