One of the best pieces of advice we can all give you is to buy the best car you can afford. Going cheap on the initial purchase will always cost you much more in the long run than if you had just spent more money up front. Without any details on the condition of the car, I feel comfortable guessing you'll drop at least another 10,000 to get it driveable and interior/exterior work. It's very tough to get your money back out. If you have a rare big block C3, you have a shot. But only if completely original. And that is even more expensive to redo (provided the big parts are there).