Looks like you may have a cowl problem. The windows have condensation on the inside. (or it looks that way in the photo.) That's usually a tell tell sign . I would at least check it, especially if your gonna keep it outside!!
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That's something I meant to tell you - forgot when I read the part about "no rust". Pour some water in to the cowl area and see where it ends up. If any ends up inside of the car don't buy the car - very expensive repair job.
The car is in AWESOME condition, it looks as if its just been completely redone with ALOT of new parts on it.
Thats what Ive heard, since Ill probably put a new system in, whats the best way to go? I want somthing that really sounds nice, I dont care if its loud...