Want a machine, want to play with it, but not to live with it

Hello! I am a former anycubic mega s victim, got it gifted by a friend(because he didn't use it) and got sucked into the rabbithole of 3d printing. Printed a few parts after calibrating and cleaning it up, but then got punched in the face with onslaught of problems that dont make sense. Tried to fix 'em all, but in result just didn't get to print anything for long. Now it shortcircuits itself when it starts up. So gonna salvage the thing for what I can.

In the meanwhile, I want to find a machines to look at that will increase my skills and knowledge further, not to just shortcut to just print stuff. Having available database of known problems will help a lot, that was the main issue I had with the mega S. Also something not expensive like the prusa mk4.(less than 400$ probably) Any recommendations for such a machine?

Sorry for such a question, if there are treads on reddit or lemmy, send me links to them, I will be happy to read them!