An Arizona residential purchase agreement is a legal document outlining the terms and conditions for a buyer's purchase of residential property from a seller. An Arizona purchase agreement facilitates the sale of real estate for an agreedupon price between the buyer and seller.Download a free Arizona residential purchase agreement template outlining terms for buying and selling property. BUYER agrees to purchase and SELLER agrees to sell the real property, and the improvements thereon, commonly known as: , in the County of. A purchase and sale agreement is a contract between a buyer and seller for transacting a property in exchange for a specific price. This FSBO paperwork is needed as soon as you accept an offer, so it's useful to have a purchase agreement onhand that you can fill out quickly.