Wash. Rev. Code § 35.48.030
The purchase of any such bonds or warrants shall not relieve the local improvement or condemnation award fund from which the same are payable from liability for payment of the same, but the city or town upon purchase thereof shall become subrogated to all the rights of the former owners thereof and may proceed to enforcement of said bonds or warrants as any owner thereof might do. The city or town may sell any property acquired by it in such proceedings upon such terms and for such prices as it sees fit, or it may resell any of the bonds or warrants for such prices as it shall fix.
Any excess in any local improvement district fund or condemnation award fund which will average a payment of one dollar to each payer into said fund shall, after payment, retirement, or cancellation of all bonds or warrants payable from said fund, be refunded and paid to the payers into the fund in the proportion that their respective assessments bear to the entire original assessment levied for such improvement, and any unpaid assessments, or portion thereof, shall be reduced in the same proportion. Any proceeds derived from the sale of any bonds or warrants, or from the sale of real estate, shall be placed in the revolving fund.
RCW 35.48.030