The annual exclusion (for 2022) is $16,000 per donor to each donee.
That means you and your wife can give your son a total of $32,000 in 2022 without being required to file a 709. Anything above that figure, however, would require gift tax returns to be filed.
If you do not want to spread the gifts over several years, you could give your son $32,000 and take back a loan for the balance ($68,000) and then forgive $32,000 each of the following tax years.
There are other strategies and you might want to seek an in-person consultation with an estate planning attorney.
https://www.avvo.com/estate-planning-lawyer.html
