When someone offers to help you make a down payment on a house, your lender will require a gift letter for a mortgage. Here's what it includes.A down payment can be hard to come by. One option is to be gifted the money, but this has certain requirements, such as a gift letter. If you go through a bank they will provide the gift letter form to you to get completed. If someone provides a handwritten letter it is filed away. Demystify gift letters in NYC real estate. Understand how to document a gift from family or friends for a smoother property transaction. However, when using gifts for a down payment, you should be aware of some mortgage gift rules for you and the donor. Gifts letters are common in financing the down payment for a home.