This page includes forms, fees, and instructions for all domestic business entities, foreign and domestic Registered Agents, and Washington Trademarks. The documents you need to buy or sell a business depend on the structure (discussed here) and complexity of the deal as well as its specific terms.A Business Purchase Agreement is a contract that transfers a business entity from its owner to a new buyer. A purchase agreement is a form used for making an offer on a home. It contains a set of conditions and contingencies that are presented to the seller of a home. Speed up the sale process - have the agreements in place early. A Sales and Purchase Agreement (SPA) is a legal contract that details the agreement's terms and conditions. Download our business purchase agreement templates for free, and ensure that you have a smooth and easy sale process.