Wash. Rev. Code § 18.11.230
Auction proceeds due to a client that are received by the auctioneer or auction company and not paid to the client within twenty-four hours of the sale shall be deposited no later than the next business day by the auctioneer or auction company in a trust account for clients in a bank, savings and loan association, mutual savings bank, or licensed escrow agent located in the state. The auctioneer or auction company shall draw on the trust account only to pay proceeds to clients, or such other persons who are legally entitled to such proceeds, and to obtain the sums due to the auctioneer or auction company for services as set out in the written contract required under RCW 18.11.130. Funds in the trust account shall not be subject to the debt of the auctioneer or auction company and shall not be used for personal reasons or other business reasons.
RCW 18.11.230