No, you do not have to wait for three strikes. RCW 59.20.080 (1) (a) allows a landlord to serve a 15-day notice to comply or vacate for material violations of the park rules or tenant’s duties under RCW 59.20.140. Mediation is required with certain timelines and procedural requirements. The mediation notice should be sent the same time as the 15-day notice. RCW 59.20.080 (1)(a) If you mediate with the tenant, and the tenant complies with the mediation agreement, the law considers the violation cured. If the tenant does not attend mediation or breaches the mediation agreement, you may commence an unlawful detainer action.