Another vote for a used syncrowave. Syncrowaves are generally very reliable.
If you want a good basic TIG, without spending a lot of money, it is hard to beat a used Miller Syncrowave 180 or 200. I have owned both, both are good. Both have High Frequency, AC and DC, so you can weld any metal, including aluminum. Both include stick and TIG. The original version of the Syncrowave 180 is arguably better for beginners, as it has minimal controls, three switches and one knob, simple to use. The later version of the 180 (180SD) added an AC balance knob and digital displays. The 200 has lots of bells and whistles, including pulse, which I like for thin copper. The 180 is a little smaller, but both are relatively big and heavy, around 200 pounds. Figure on at least a 50 amp 220V circuit for either welder, which is what I use. Some recommend a 60 amp 220V breaker.
I bought the 200 for $1300, too good a deal to pass up, and then sold my Synchrowave 180 for $1150. The 180 price that I got was probably higher than average, and the 200 price that I paid was lower than average, so I did very well, paid only $150 to upgrade.
Anyway, for somewhere between $1000 and $1500, you can buy a used Syncrowave 180 or 200, and have a welder that will probably serve all your needs for decades. If you buy used, and you decide you need a bigger or fancier welder down the road, you can get almost all your money back when you sell it. You will take a big depreciation hit if you buy a new welder and sell it later. With these Syncrowaves you can TIG weld any thin metal up to about 3/16 inch, and you can stick weld any steel 1/8 inch or thicker. I used the 180 as a stick welder for months before I got around to buying an argon bottle. Some report that the 180 had a higher than average repair rate, but my original version 180 gave me no trouble.
I am not a big fan of the Miller Diversion because it lacks stick. Stick is what you need to weld thick steel. The Dynasty is a great welder, but way too much money unless you have to have easy portability, or need 110V. (Note that a 20 amp 120Volt outlet will only run a welder at very reduced power, so 110V operation is not that great an advantage). The Miller EconoTIG looks good on paper, but a Miller factory guy said that it was not that great, that the Syncrowave 180 was a much better machine. Lincoln makes the Square Wave 175, and Precision TIG 225, similar to the Syncrowaves, look for a used Lincoln as a possible alternative. Many if not most inverter welders are DC only, so you can’t TIG aluminum. (Examples: Multimatic 200, XMT series, Maxstar series, the new Thermal Arc multi-process welders, Lincoln V350 and C300, etc.)
Note that many inverter welders, such as the Dynasty or Invertec series, do not come standard with a TIG torch, regulator, and foot pedal, so they are even more expensive than they look at first glance. The Syncrowaves come with everything you need except a gas bottle. The welder manufacturers are pushing their inverter machines, but it is hard to justify the much higher cost, especially when you can find a used Syncrowave for not much more than $1000. They have sold a lot of Syncrowaves, so you should be able to find a used one if you look.
Just for comparison, a new Syncrowave 200 retails for $2900, a new Dynasty 200DX with torch, regulator, foot pedal, etc., retails for $4680. On the used market, the Dynasty 200 welders are hard to find, and priced around $3000. The Syncrowaves are easier to find used, and priced right.
The Syncrowave 250 is an industry classic, a great machine, but big and heavy, and more expensive. It should probably have a 100 amp 220V circuit, especially if you want to get full power out of it. The 250 is just more welder than most folks need, unless you need to TIG 1/4 inch thick aluminum.
