Wash. Rev. Code § 59.18 § 59.18.310

(1) If the tenant defaults in the payment of rent and reasonably indicates by words or actions the intention not to resume tenancy, the tenant shall be liable for the following for such abandonment: PROVIDED, That upon learning of such abandonment of the premises the landlord shall make a reasonable effort to mitigate the damages resulting from such abandonment:
(a) When the tenancy is month-to-month, the tenant shall be liable for the rent for the thirty days following either the date the landlord learns of the abandonment, or the date the next regular rental payment would have become due, whichever first occurs.
(b) When the tenancy is for a term greater than month-to-month, the tenant shall be liable for the lesser of the following:
(i) The entire rent due for the remainder of the term; or
(ii) All rent accrued during the period reasonably necessary to rerent the premises at a fair rental, plus the difference between such fair rental and the rent agreed to in the prior agreement, plus actual costs incurred by the landlord in rerenting the premises together with statutory court costs and reasonable attorneys' fees.
(2) In the event of such abandonment of tenancy and an accompanying default in the payment of rent by the tenant, the landlord may immediately enter and take possession of any property of the tenant found on the premises and may store the same in any reasonably secure place. A landlord shall make reasonable efforts to provide the tenant with a notice containing the name and address of the landlord and the place where the property is stored and informing the tenant that a sale or disposition of the property shall take place pursuant to this section, and the date of the sale or disposal, and further informing the tenant of the right under RCW 59.18.230 to have the property returned prior to its sale or disposal. The landlord's efforts at notice under this subsection shall be satisfied by the mailing by first-class mail, postage prepaid, of such notice to the tenant's last known address and to any other address provided in writing by the tenant or actually known to the landlord where the tenant might receive the notice. The landlord shall return the property to the tenant after the tenant has paid the actual or reasonable drayage and storage costs whichever is less if the tenant makes a written request for the return of the property before the landlord has sold or disposed of the property. After forty-five days from the date the notice of such sale or disposal is mailed or personally delivered to the tenant, the landlord may sell or dispose of such property, including personal papers, family pictures, and keepsakes. The landlord may apply any income derived therefrom against moneys due the landlord, including actual or reasonable costs whichever is less of drayage and storage of the property. If the property has a cumulative value of two hundred fifty dollars or less, the landlord may sell or dispose of the property in the manner provided in this section, except for personal papers, family pictures, and keepsakes, after seven days from the date the notice of sale or disposal is mailed or personally delivered to the tenant: PROVIDED, That the landlord shall make reasonable efforts, as defined in this section, to notify the tenant. Any excess income derived from the sale of such property under this section shall be held by the landlord for the benefit of the tenant for a period of one year from the date of sale, and if no claim is made or action commenced by the tenant for the recovery thereof prior to the expiration of that period of time, the balance shall be the property of the landlord, including any interest paid on the income.
(3) This section does not apply to the disposition of property of a deceased tenant. RCW 59.18.595 governs the disposition of property on the death of a tenant when the tenant is the sole occupant of the dwelling unit.