The person gifting the vehicle must complete a sales tax exemption form (MVU-24). A gift letter must contain the donor's name, the gift's value, confirmation that the gift is not to be repaid, and the donor's signature.In order to be exempt from the sales and use tax, you must meet the requirements of the law and complete the affidavit above. A gift letter is an important, formal, legal piece of documentation that can help explain that a (usually rather large) sum of money was gifted to you. The letter must explain who is gifting the money, where the donor's funds are coming from and the relationship between the donor and the recipient. A mortgage gift letter is a document that helps satisfy the requirement that a borrower's down payment funds come from legitimate sources. Yes, all lenders will require a gift letter. Although you may have the funds, the lender needs to confirm that you won't have to repay the gift.