Mich. Comp. Laws § 445.1927

Sec. 7. (1) A manufacturer shall from time to time publish its prices, charges, and terms of sale for recreational vehicles and may only sell a recreational vehicle to a dealer in accordance with the published prices, charges, and terms of sale in effect at the time of sale. (2) If a manufacturer offers a dealer a rebate, discount, or program on any recreational vehicles, the manufacturer must offer the same rebate, discount, or program to every similarly situated dealer. (3) In a renewal of a dealer agreement, the manufacturer may not impose on the dealer additional inventory stocking requirements or retail sales targets in excess of market growth in the dealer's area of sales responsibility.