This is a loan the seller makes to the buyer to facilitate the sale. You also need a collateral agreement (often called a UCC filing) if the sale includes physical assets.Seller's interest in the Property includes: (1) Loss. Buyers shall purchase as part of this contract, all equipment, fixtures, goodwill, inventory, trademarks, trade names, and leasehold rights. When you are included in the lien sale, the City of New York sells your debt to an authorized buyer. The buyer then has the right to collect what you owe. You will need a promissory note and security agreement that addresses the key terms of the seller note.