Thinking about getting a welder

Anything that will run on a 115 will get you what you want, but I would use an inert gas to shield the welds from contamination. ARC welding is dirty, as are flux core wire feed welds. They can be used for some things, but structural or sealing parts, like oil pans, valve covers, etc should not be welded with them.

Millers are a little on the high end for price range, but I would expect to pay about $600 or so for a used one. Hobart is also a fantastic machine that has plenty of parts and customer support representation behind it for a MIG machine. You can do just about anything you want with a 110 MIG that is set up with gas. You may have to channel the heavier parts a bit to weld them with a 110 and make multiple passes, but it depends on trial and error.

It's best to follow the suggested settings on or in the welder for metal. Most 110 machines will do up to 1/4" mild steel.