Buy a Chinese TIG off eBay, but shun the 110v and the combo (+plasma) units.
I got very lucky (knock knock) with an orange Hutai brand 220v/200a/pulse machine for $350. (but the seller hid the brand name until I got the welder and could read it on the case.) Although the workmanship inside is obviously cheap, I baby it (lives in the house until needed,) and I've never had it shut down during kart work (which is sporadic, and all I do.) It would probably not be acceptable for a pro using it every day on jobs.
If your house will support a clothes dryer you have a 220v line readily available. ALL electric service is at least a 220v (i.e., 2-phase, split into two 110v circuits) line. Learn about it. On every (at least 220v) welder you need to choose, buy and install a plug anyway. They usually come without one, just a bare wire. IMO 110v welders just aren't stable enough, even though you may not need the extra current for kart work. Of course an expensive welder, like the vastly preferable small Miller machines, will also be stable at 110v, but they're well over $1K.
TIG welding is so clean, precise and confined, that you can safely do it on your kitchen or dining room table.
(- of course you wouldn't, as it also involves lots of grinding, filing, fitting and cutting of metal beforehand...) And once you weld your piece it's usually VERY hot. But the "arc" itself is tiny, contained in a gas (you need argon) envelope, and soooo precise. There are NO sparks or slag with TIG.
