don't bother with abs - which means you don't need an enclosed machine :-)
And $500 gives you scope for some decent i3's (ie: not enders lol)

this is a decent looking machine:https://www.amazon.com/ADIMLab-Assem...463181&sr=8-21

Has the three key elements of a GOOD I3:
direct drive extruder, print bed side supports and dual z motors.

Also worth looking at the prusa mini.
Probably the most advanced electronics on an i3. Not as large a print volume but a rock solid plug and play printer.
https://www.prusa3d.com/original-prusa-mini/

After about 20 minutes of leafing through amazon I can't find anything better value than the adimlabs.