Wash. Rev. Code § 7.100.060
(1) When a property has been the subject of foreclosure, a county, city or town may notify the grantee of the trustee's deed or sheriff's deed, via certified mail, that a property is a nuisance. Upon receipt of such a notice, the grantee of the trustee's deed or sheriff's deed shall respond within fifteen calendar days and provide one of the following responses:
[ 2018 c 306 s 15.]