When purchasing your home, one of the most important documents that you will review and sign is the Agreement of Sale (AOS) contract. This is going to be how to fill out the agreement of sale for pennsylvania.The catchall heading of buyer actions that result in a termination in which the buyer loses deposit money is "buyer default". MV Realty requires homeowners to sign a mortgage putting up their home as a guarantee for any money due under the agreement. We can guide you through the process. Talk to Our Experienced Legal Team Today. Fill Out the Form Below or Call Our Firm at (215) 486-0123. In the initial stage, state laws govern the requirements for a valid contract, including real estate contracts such as mortgages. An oral contract is made up of a verbal offer and verbal agreement. All rights reserved.