A commercial real estate purchase agreement is a legal document between a buyer seeking to purchase commercial property from a seller for an agreed-upon price. The heart of this journey lies in the Commercial Real.Estate Purchase Agreement, a legally binding document outlining the terms of the transaction between. In this video, Ron Rhode will be going over the A.CRE Office Purchase and Sales Agreement free real estate template. 3. Property. Fill out the street (physical) address of the property the buyer is purchasing. Include any unit or apartment number, if applicable. An attorney's explanation of an Office Purchase and Sales Agreement and its free template for commercial real estate.