If the machine is working, the price is good. Most of the information you require should be on the plate on the front of the machine(look for primary input voltage and amperage) or elsewhere, but it is probably going to require a 220V input with a 50 amp breaker to obtain near maximum output, so make sure your wiring is adequate, or be prepared to modify it. (Cost will depend on your present situation and ability).

Linde was an old and respected manufacturer, and was taken over by Esab, so you might find some information at their website. ("The Linde Group", is a recent revival of the name by a chain of LWS's that took over BOC).

Also, this machine appears to be AC only, so it is limited, compared to AC-DC machines.

You can find a Miller Thunderbolt AC/DC on craigslist for $200 and that gives you more rod options -vs- the AC only machine. I've had my Thunderbolt since 1998 and have run a ton of welding rod with. It has been sitting unused for years though but when I plugged it in a week or two ago she welded like I remembered, no issues or problems. An AC/DC machine will be your best money spent. Getting the AC only one and you'll find yourself limited quickly. Besides a AC/DC machine opens up the whole world of TIG for you as well.

On your electrical I ran a 10/3 wire around 25 feet from my breaker box with a 70 amp breaker for the 220. Wire was the most expensive part. I dropped a plug on one of the support columns in the garage and that's where the machine sat for years. I'm no electrician but the internet is vast and if I can find out info on the web or call my electrician sister and save the cost of an electrician you can bet I will!