Does a gift letter need to be signed by a lawyer? -

Im in the process of writing a gift letter for a friend to give him money for a down payment. is it necessary to have a lawyer sign it?

NOT at all. Signature of donor. Notary puts seal on paper that the person s signature is the person named in document. Go to your bank or currency exchange to get document notarized.

if it is a gift and you do not expect him to pay you back then no you just need to get it notarized rather its a gift(him not paying you back) or a loan(required that he pays it back) they just need to be notarized to cover both parties

You just need a notary.