Set up the payment schedule for your sellerfinanced loan. A Business Bill of Sale is a legal document used to transfer ownership of a business from a seller to a buyer.Seller financing allows business buyers and sellers to remove the middleman (bankers) and work together directly to come up with a funding deal. Purchase Agreement: A legally binding document detailing every aspect of the sale. A purchase agreement that lists items of personal property that requires a bill of sale, since lenders are not in the business of financing personal property. REAL ESTATE TAXES: Real estate taxes due and payable in the year of closing shall be prorated between Seller and. A business purchase agreement is a legal contract specifying terms for buying or selling a business, including conditions and obligations.