Use a California business purchase agreement to record the sale of a business. Download your free template today.This PURCHASE AND SALE AGREEMENT AND ESCROW INSTRUCTIONS. Please also review the separate Contra Costa County or city specific Ordinances and Regulations for property in the area you are either selling or buying. Buying or selling a business can determine your future. Make sure it is sound. Purchase price is not a simple calculation based upon square footage but an agreement as to what Buyers will pay and what Sellers will accept. Identify the parties involved in the transaction. 2.