This is a template for an addendum that supplements a standard contract of sale for residential real property in Massachusetts and can be used by buyers and sellers. The addendum is intended to be attached to one of the most commonly used preprinted templates of purchase and sale agreements prepared by the Massachusetts Realtors Association (MRA), the Greater Boston Real Estate Board (GBREB), and the Real Estate Bar Association (REBA). The template contains practical guidance, drafting notes, alternate clauses, and optional clauses. The parties can and should modify the standard agreement and include different provisions from this addendum depending on the facts of the transaction and which standard template is used. The MAR and REBA templates are more buyer-friendly, and the GREAB template is more seller-friendly. For more information on drafting residential real estate purchase and sale agreements, see Purchase and Sale of Residential Real Property (MA). For a list of resources on residential real estate transactions in Massachusetts, see Residential Purchase and Sale Transactions Resource Kit (MA). If this addendum is used, the final provision of the template purchase and sale agreement should incorporate the addendum by reference into the purchase and sale agreement.