Ha there's no way dude for 50$. I bought a longboard from 1986 a while back. It had 5 dings on each rail, the fin box was totally broken and the tail had a ton of fiberglass missing. I had a ton of fiberglass work to do.
Thats me putting in the fin box.I got it for 80$. If you find one on steep and cheap do NOT buy anything shorter than 8 feet long. Trying to learn on a shortboard is really difficult and you will not have any fun.
I hate to shit on your parade
Until you can get up, make a turn at the bottom and ride the wave down the line don't even worry about buying a board. Your gonna want to learn on an 9 foot foamie and as soon as you can ride down the line that thing will be no fun anymore and THEN you buy a board. I promise you!!