Purchase and Sale Agreement. A purchase and sale agreement is a contract between a buyer and seller for transacting a property in exchange for a specific price.This attachment should be given to the Buyer prior to the submission of any offer and is not part of the Residential Resale Real Estate Purchase. An Arizona purchase agreement facilitates the sale of real estate for an agreedupon price between the buyer and seller. 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. A purchase agreement is a legal contract between a buyer and a seller. To avoid a worstcase scenario, follow these pointers on drafting a contract that guards your interests as the seller and financier. 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.