RCW 63.14.100: Receipt for cash payment—Retail installment contracts, statement of payment schedule and total amount unpaid.

A buyer shall be given a written receipt for any payment when made in cash. Upon written request of the buyer, the holder of a retail installment contract shall give or forward to the buyer a written statement of the dates and amounts of payments and the total amount unpaid under the contract. Such a statement shall be given the buyer once without charge; if any additional statement is requested by the buyer, it shall be supplied by the holder at a charge not in excess of one dollar for each additional statement so supplied.