The IRS taxes gifts made over a certain dollar amount. A gift letter is a piece of legal, written correspondence explicitly stating that money received isn't expected to be repaid.A gift letter is a note from a donor to your lender regarding cash funds for your mortgage down payment. One, a gift is not taxable for the donor or donee unless it exceeds lifetime gift tax exclusion during their lifetime. Documentary stamp tax is an excise tax imposed on certain documents executed, delivered, or recorded in Florida.