This fill-in-the-blank form can be used to change or extend inspection, signing, financing or other dates contained in a signed real estate contract. There are two main offer forms used in Massachusetts.Upon written notice to the BUYER or BUYER'S agent of the SELLER'S acceptance, the accepted Offer shall form a binding agreement. An Offer to Purchase is a legal document that outlines the terms and conditions of a real estate transaction. I wanted to walk through the basics of putting together an offer for you today. A binding contract requires both an offer and acceptance of that offer. From: ("Buyer") TO: ("Seller"). What are the elements of a valid contract in your jurisdiction? To create a valid contract under Massachusetts law, there must be: • An offer.