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King County Department of Assessments

Fair, Equitable, and Understandable Property Valuations

Department of Assessments

500 Fourth Avenue,
Suite ADM-AS-0708,
Seattle, WA 98104

Office Hours:
Mon - Fri
8:30 a.m. to 4:30 p.m.

TEL: 206-296-7300
FAX: 206-296-5107
TTY: 206-296-7888

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Glossary of terms for commercial parcels

MASS APPRAISAL
The process of valuing a group of properties as of a given date, using standard methods, employing common data, and allowing for statistical testing.

MASS APPRAISAL MODEL
A mathematical expression of how supply and demand factors interact in a market.

MISCELLANEOUS INCOME
Income from sources other than actual rent (parking, laundry facilities vending machines and so on).

MODEL
(1) A representation of how something works.  (2) For purposes of appraisal, a representation (in words or an equation) that explains the relationship between values or estimated sale price and variables representing factors of supply and demand.