The answer is: Depends! I've seen a few of these cars that are ultra garage queens - 1,000 miles or less, and some are fine but others have some strange things going wrong simply from setting up. I would check the oil and if it looks ok then it probably is, but I would change it as soon as I got the car. Then the only question is did the owner start it enough to circulate the oil from time to time, and then do you trust his answer. Drive the car - you can tell a lot from driving one. Make him start it up with you watching the exhaust - any smoke? In other words, treat it just like any other used car when checking it out. As far as the value, $55k would be high for an '07 standard Z with that low maileage - more like $48k would be a good price. It being a Ron Fellows Z, it would be worth more if it were in perfect condition. Just my opinion, but I would thing maybe $52k. Another way to price it would be to add the same percentage higher that you would have had to pay over the standard Z when it was new. If that were 10 percent, Take the $48k and add 10 percent ($4.8k), or $52.8K. That's kind of depreciating the price difference similarly to the depreciation of the rest fo the car. That might make the price come out closer to the $55k. Do your homework!