Massachusetts Offer to Purchase Real Estate Form âś“ easily fill out and sign forms with PDFLiner âś“ download blank or editable online. This file contains detailed instructions for completing the NWMLS Form No. 21, a Residential Real Estate Purchase and Sale Agreement.Forms are state specific because real estate laws vary significantly from state to state. 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. A. Offer to Purchase sets forth buyer's offer of price, date for closing, contingencies for inspections, financing etc. Fill out the following form below and we send you a zero obligation cash offer within 24 hours. We will never share or sell your information. One type of contract, which is not a standard contract, is a drafted or generic contract. If the seller accepts the offer, there is an agreed period of time to negotiate the actual contract, called a Purchase and Sale Agreement.