10409 Beardslee Blvd, Bothell, WA 98011

Office · Bothell · Seattle-Bellevue metro, WA

One of 82 reachable office buildings in Bothell. Larger than 54% of office buildings in Bothell (median 5,724 SF), derived from assessor records.

Usable building area
7,476 SF, King County Assessor
Lot size
24,560 SF, King County Assessor
Year built
1964, King County Assessor
Stories
1, King County Assessor
Predominant use
Office Building, King County Assessor
Assessed value
$2,948,200, per the King County Assessor (not a market appraisal)
Assessed value per usable SF
$394.36/SF, derived from assessor records
Usable area / lot
0.3, derived from assessor records
Vintage
1960s vintage
Zoning
DN, King County
County use code
Office Building

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

MakeMe Estimate: $3.87M (estimated market value), with a likely range of $3.24M to $4.71M (half of recent verified sales in this segment landed inside that range). Based on 8 verified arm's-length comparable sales (through 2026-06-01). The county roll carries a nominal improvement value for this parcel, so the estimate leans on comparable sales and the county-confirmed building area rather than the county land and improvement split. Not an appraisal. How this estimate works.

moderate confidence: 5 comparable sales within 3 miles; nearest 0 mi. This property type carries wider measured error; treat the estimate as a starting point. Last arm's-length sale: $2,900,000 in 2021. The market has moved since; the estimate reflects current county values and ratios, not that price.

Comparable sales used as evidence

Recorded arm's-length sales of similar buildings nearby; nearer and more recent sales rank first. Buyer and seller names are withheld. Get this data via API.

Market context: Office in Bothell

median verified sale $449.48/SF over the trailing 24 months; 5 sales in the last 12 months and 5 in 24 (newest verified sale 2025-12).

  • 2021: $387.91/SF median (4 sales)
  • 2025: $449.48/SF median (5 sales)

Computed from 96 verified arm's-length sales in King County public records (5 in the trailing 24 months). Free public records. Not an appraisal.

Last sold: 2021-03-18 for $2,900,000 (recorded arm's-length sale).

Current ownership dates to 2021 (about 5 years) per recorded transfers.

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

Value over time

$0$2M$4M$6M201120142017202020232026Last sold $2.9M · 2021$3.87M$2.95MCounty assessed valueMakeMe Estimate rangeRecorded sale

Dark line: county assessed value per King County tax rolls. Blue line: our estimate; dashed years are a modeled backcast built from recorded arm's-length sales in the building's segment, not estimates published at the time, and years without enough sales stay unmodeled. The shaded range is the model's measured error band; about half of verified sales in the segment land inside it. Diamonds: recorded arm's-length sales. Not an appraisal. How this estimate works.

Land, site, and value history

Assessed value moved from $1,146,800 (2011) to $2,948,200 (2026), up 157% over 15 years, per county tax rolls. The 2026 roll splits $2,948,200 into $2,947,200 land and $1,000 improvements.

Taxes