3 big strong hunky men can turn a Wayfarer over although if space is tight I would make it 4 to be sure. – my three sons can turn the boat over and carry it back into the shed and put it onto 3 solid peat bales ready for painting. But we do have a lawn (of sorts) on which to turn over onto. I would help but they say that they work together like a well-oiled machine and I am the bit of grit (their father is a handful of sand) 😯 so I let them get on with it now
hope that helps