You also want to take the duty cycle time of the welder into consideration. I'm too tired to try and explain, so here's a link to read...
https://www.markthewelder.co.uk/id51.html
I was a certified high pressure vessel welder in the Navy and we mainly used Miller Maxstar welders. We mainly used them to stick and TIG weld. We had the capabilities of adding on a MIG welder, but it wasn't a welding process we used. If you plan on learning I would suggest you buy a decent welder. You don't want to start with junk because you will learn bad habits which will be hard to get rid of.
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