(a) Except as authorized under RCW 46.55.037, ask for or receive any compensation, gratuity, reward, or promise thereof from a person having control or possession of private property or from an agent of the person authorized to sign an impound authorization, for or on account of the impounding of a vehicle;

(b) Be beneficially interested in a contract, agreement, or understanding that may be made by or between a person having control or possession of private property and an agent of the person authorized to sign an impound authorization;

(c) Have a financial, equitable, or ownership interest in a firm, partnership, association, or corporation whose functions include acting as an agent or a representative of a property owner for the purpose of signing impound authorizations;

(d) Enter into any contract or agreement or offer any program that provides an incentive to a person authorized to order a private impound under RCW 46.55.080 that is related to the authorization of an impound or a number of impounds.

(i) The incentives prohibited by this section may be either monetary or nonmonetary things of value, such as gifts or prizes which are contingent on, or as a reward for the authorization of impounds.

(ii) Gifts of de minimis value that are given in the ordinary course of business and are not tied to any specific decision to authorize an impound or impounds are not prohibited. Permitted gifts would include promotional items such as pens, calendars, cups, and other items labeled with the registered tow truck operator's business information, holiday gifts such as cookies or candy, flowers for occasions such as illness or death, or the cost of a single meal for one person when discussing business.

(iii) The provision of the actual physical signs required by this chapter to be posted on private property and the labor and materials for placing them is not a violation of this section.

(b) A convenience fee, as permitted by law, to be paid by the credit or debit card user whenever a credit or debit card is chosen as the payment method for the costs of towing, storage, tolls, or ferry fares. The fee must be sufficient to offset the charges imposed on the tow truck operator by the credit and debit card companies or card processors but shall not exceed four percent; or

(c) The costs of other services rendered during the course of towing, removing, impounding, or storing of an impounded vehicle as provided by RCW 46.55.120.