Since they're being given to ya, why not! Just don't go out buying a bunch of parts until you've corrected the iron cancer.

I do agree with Bob, the flux core welders are great for patching minor jobs around the barn, but for auto sheet metal, you'd be far ahead to spend $300 and get a nice (gas) mig. Harbor Freight has one that several of my friends have purchased and all are happy with. I thing they gave just under $300 for them.

Myself, I guess I'm lucky. We've had every metal fabricating supply we could need for as long as I can remember. Not so lucky I guess, I used the tools when ever I needed b4, but now that it's all mine, kinda sucks (grandfather died and I inherited it).

I've done several cars in very bad shape. I've never done a Volvo in such bad shape though as I haven't run across one. Only minor stuff on Volvos. However, I think I could fab and replace the under carrige of a 280zx in my sleep. Sheesh they built some biodegradable cars. I'm working on an 82 280 now. The previous owner went to jack it up and the jack went through the metal (rust).

The main thing is to take your time. When you cut a repair panel, cut it well larger than what you actually need. Then when you trial fit it you'll miss the most common mistakes made.

Best of luck