The Buyer undertakes to pay the total price which appears in the present Contract. In the five boroughs of New York.City, mortgage recording tax for substantial commercial mortgage loans is generally 2.8 percent—often the largest transaction. A sales contract is an agreement between a seller and a buyer for an agreed upon price and other terms for a product or service. Learn the steps in a real estate transaction and what happens with sale of property. Find a real estate lawyer. An international sales contract is an agreement between a buyer and a seller that identifies the parties in the transaction, the goods or services being sold. Title Defects; Purchase Price Adjustment; Materially Adverse Agreements. Examples of SPAs in the Marketplace. One of the most common SPAs occurs during real estate transactions.