I printed out my Tax papers and every is about 25 pages, I folded them in half and stuffed them in a large envelope, I have no idea how many stamps I need though? I have about 7 forever stamps on me. It roughly the weight of a dvd stuffed into an envelope.
go to a post office or buy a postage scale. I've found that mail with insufficient postage never gets delivered and is never returned to the source. even better, since the USPS is having trouble timely delivering mail. get tracking info so you know it got to where it was sent.
question: if is this is a 2020 return why aren't you e-filing which will speed up your refund if you are due one.