I see a Creality Ender 3 V3 (not SE or KE) for $130 refurbished, and also a Creality CR-10 SE for $103 refurbished on ebay. Are either or these a good choice to get into the hobby, or am I making a mistake? Should I rather buy a Bambu? My budget is around $100-$200 max. Please advise.
Not a mistake, I’ve got an ender 3 and a cr10. Both are fine, keep your expectations realistic and calibrate each axis, especially the extruders. Use PLA, consider getting a new build plate if your prints won’t stick. I recommend flashing firmware on the ender 3 unless you know what was loaded onto it last, doesn’t have to be fancy firmware just something you know for sure is configured for your printer. A cr10 should probably get firmware as well but I never loaded new firmware on mine and the controller is older so I’m not sure if it’s a good idea.
Don’t forget the cost of filament, if you print a lot you may spend more on filament in a year that your printer budget.