For a cheap and portable MIG welding machine when you need to make running repairs, check out the Goplus.
With its limit set at thin steel and iron, this should be $130 well spent, as long as you don’t expect more heavy-duty results. As a flux core welder, it’s easy to use, and you also get adjustable flow settings. It is a mini, but don’t let that put you off, this cheap MIG welder is a hard worker when it comes to sheet steel. The weld you lay may not be the most precise but for the money, you should be happy. You also get some nice additional safety features such as side air vents to help with heat dissipation, overheat protection circuit and a basic safety mask.