In most realestate transactions in Washington, the seller of the property must complete a "Form 17" disclosure statement and give it to the buyer. 020) since January 1, 1995.By law, most sellers of real property must provide a completed Seller Disclosure Statement (aka Form 17) to any buyer. Withing five days of accepting the buyer's offer, the seller must provide the buyer with a Seller's Disclosure Statement, also called "Form 17". To be used in transfers of improved residential real property, including residential dwellings up to four units, new construction,. _day of April, 2017, between. Clark County ("County ..), a political subdivision of the State of Washington, and the Cowlitz. O Fill out each form completely. These forms are not a substitute for legal advice and if you have difficulty filling out these forms, then you may wish to consult with an attorney.