N.Y. Gen. Bus. Law § 21

§ 21. Commissions; penalty. An auctioneer in any county, other than\nNew York or Kings, shall not, without a previous agreement in writing,\nwith the owner or consignee of the goods sold, demand or receive a\ngreater compensation for his services than a commission of two and\none-half per centum on the amount of any sale, public or private, made\nby him. For a violation of this section he shall refund the moneys\nillegally received and forfeit two hundred and fifty dollars to each\nperson from whom he demands or receives an unlawful compensation or\ncommission.\n