Upload & Sell: Off
Cheap underwater camera?! Now there is an oxymoron if I have ever heard one! Very slippery slope you are on. The word underwater seems to miraculously add zeros to the cost of items in a record rate.
My experience was: Went on a trip and did some snorkeling, liked it. Tried diving($), loved it. Then got certified for diving ($$), then better camera (G9 + Canon housing $$), then more diving ($$), then advanced certification ($$), then diving gear ($$$), then more trips ($$$), then better dive computer($$$), then nitrox certification ($), then better camera ($$$) + better housing ($$$) + strobes($$$) + macro adapters ($$$). You get the idea.
If you have a point and shoot camera, look to see if the manufacturer makes an underwater housing for it. Canon makes housings for a lot of their point and shoot cameras. So does Olympus. For $150 to $200 you can outfit a P&S with a good underwater housing more than sufficient for snorkeling. I used a Canon housing with a G9 for many years before recently moving to a Sony RX100 and Nauticam housing. GoPro has a specific underwater housing for it's cameras.
Good luck and enjoy.