I honestly do not think there is any money to be made in selling these things... it takes so much to clean, de-gunk, tinker... am I wrong? I must be wrong, for it seems as though some (Miriam and Joe I think) do make coin at this - but it seems to me that for the most part, you really have to just love doing it, and if you happen to break even, or not lose too much, then so much the better!
I have not sold any machines. I don't think I could just buy something and flip it. It's just not my personality to do so. The closest I have come to that is that I have found a teenage girl to give one of my machines to once I restore it. She is going to choose between the 99k and a 1924 Vinnie. :-) I had fun tinkering, and she gets a special machine. I'm too much of an amateur to consider charging for anything. :-)
That said, I am interested to know what others do! Do most people here just buy and keep? Buy and flip? Buy and fix and sell? Does anyone make a living at it, or is it more of a hobby-which-pays for itself? (I don't mean any insult by that question! I just genuinely have no idea.)