Last updated May 2026. By using this site you agree to these terms.
The cost segregation benchmarks, calculators, and FAQs on this site are informational only. They are not tax, legal, accounting, or investment advice. Cost segregation outcomes vary by property, ownership structure, tax position, and current law. Consult a qualified CPA, tax attorney, or financial advisor before making decisions based on information from this site.
The per-fixture engine outputs shown on the benchmarks page represent the engine's output for representative property scenarios. Real customer studies use real property data, real assessor records, and real renovation history, outputs for your specific property may be higher or lower. The illustrative Year-1 federal savings figures assume the 37% top marginal bracket and 100% bonus depreciation; actual savings depend on your taxpayer profile.
City of Seattle Short-Term Rental Ordinance restricts STR operations to primary residences with operator presence, non-primary-residence absentee STR operation is largely prohibited within Seattle city limits. Adjacent jurisdictions: Bellevue, Kirkland, Redmond, Renton, Kent each operate distinct STR rules, some permissive, some restrictive. King County unincorporated areas operate lighter regulation. For STR-intent buyers, the jurisdictional verification matters more than the cost-seg study itself. WA B&O excise tax applies to gross rental receipts, Class A apartment rental, Class B residential rental, and other classifications carry different rates. Material participation under §469 for non-STR rentals requires real-estate-professional status, full-time Seattle tech employees rarely achieve the 750+ hour annual test, but a non-employed spouse running the rental operations frequently can.
We re-verify regulatory facts quarterly and refresh the timestamps at the bottom of each page. Despite this, regulations change frequently. Before relying on regulatory statements for a specific decision (license status, hold-period planning, material-participation strategy), verify with the relevant authority.
The dataset published on /data/seattle-cost-seg-stats/, including the downloadable CSV and PDF, is licensed under Creative Commons Attribution 4.0 International (CC-BY 4.0). Republication is permitted with attribution.
Page content (text, images, code) outside the explicitly CC-BY-licensed dataset is © Cost Seg Smart LLC, all rights reserved, unless otherwise marked.
This site is provided "as is" without warranty of any kind, express or implied. Cost Seg Smart LLC is not liable for any decision made based on information from this site. Use at your own risk.
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