The Standard Agreement for the Sale of Real Estate should be used in transactions to outline the terms of the agreement between the buyer and seller. Use a Business Bill of Sale to set out the terms for the sale of a business and transfer the ownership and all assets to the buyer.There are at least a couple ways to seller finance: 1. Seller financing is an agreement in real estate where the seller handles the mortgage process rather than a financial institution. The most important document in an asset deal is the Asset Purchase Agreement (the "APA"). In this article, I will discuss the key provisions of an APA. Typically, this involves two documents: a financing agreement (basically a loan document outlining the details and terms of the loan) and a promissory note.