I got a Lincoln Electric SP-135 years ago for $600 - wire feed, with the solenoid and regulator if I want to do MIG (I have only used flux core in it up til now), coninuously variable feed and current (no detents at A, B, C, etc), plugs into 110 but it needs to be a 30 amp circuit or you will keep tripping the breaker when doing thick stuff.

I managed to weld 3/4" plate to 1/4" plate cold rolled steel! It's not a pretty weld but it held up when dragging the Commander as dead weight behind my brother-in-law's bulldozer to test it.