Wash. Rev. Code § 64.35.605
(4) If the parties do not jointly appoint a mutually acceptable mediator within the time required by subsection (3) of this section, the party may apply to the superior court of the county where the project is located, which must appoint a mediator taking into account:
(8) A party may attend a mediation session by representative if:
(9) A representative who attends a mediation session in the place of a party as permitted by subsection (8) of this section:
(12) At least seven days before the first mediation session is to be held, each party must deliver to the mediator a statement briefly setting out:
(14) Before the first mediation session, the parties must enter into a retainer agreement with the mediator which must:
(b) Provide that the cost of the mediation will be paid:
(18) A mediation session is concluded when:
(19) If the mediation resolves some but not all issues, the mediator may, at the request of all parties, complete a report setting out any agreements made as a result of the mediation, including, without limitation, any agreements made by the parties on any of the following:
[ 2004 c 201 s 1501.]