Any individual, business, partnership or corporation (with a few exceptions) may bring a small claims action only to recover money; a "natural person", meaning a human being, may file a claim up to $10,000; the limit is $5,000 in all other cases. In general, the claim must be filed in the district court of the county in which the defendant(s) reside.
Exceptions and specific rules can be found at RCW 3.66.040. The State of Washington may not be sued in a small claims action. Attorneys and paralegals are excluded from appearing or participating with the plaintiff or defendant in a small claims action unless the judge grants permission.