Use a California business purchase agreement to record the sale of a business. Download your free template today.This article will delve into what BuySell Agreements are, how to determine when you need one, their benefits and potential drawbacks for small business owners. 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. A well drafted buy and sell agreement is one of the most valuable tools a company can have to protect its value in the event of death, disability or divorce. A Business Purchase Agreement is a contract that transfers a business entity from its owner to a new buyer.