ok
The reason you saw one for $400 used is because the person realized it was junk and dumpped it. I have been here for a few years not and have only seen one for $400. Honestly I would not give you $10 for a new one,
Well maybe I would give someone $10 for one because I could use the light that comes with it. If all you want one for is for doing a tip from time to time for yourself. Get right pin for your shaft and put it on a drill. or pay a cue repair man $15-$20 bucks to do it right. After all how often do you need a tip put on your cue.
Good luck what ever you do, If you do get a repair lathe I think you will have a lot of fun with it, You can do a lot with it..