Wash. Rev. Code § 87.06.030
Before preparing a certificate of delinquency, the treasurer of a district that has designated its own treasurer as provided in RCW 87.03.440, shall provide to the board of directors a list of properties that may be subject to foreclosure for delinquent assessments. The board of directors shall review the list of delinquent properties. After comparing the amount of the delinquent assessment with the costs of foreclosure, including but not limited to title search, court filing fees, costs of service, and attorneys' fees, the board of directors may determine that it is not in the best interest of the district to commence legal action to foreclose the delinquent assessment liens. Nothing in this section precludes a county treasurer from proceeding with foreclosure on parcels otherwise delinquent and, in those actions, from collecting delinquent assessments due under this title.
RCW 87.06.030