With only 29,000 miles on it the car is probably worth around $6,000-$7,000 if it were stock depending on the condition. With the mods it may be worth $11,000, but you could buy a nice used Cobra for that. If the car looks and runs as nice as it sounds go for it. I wouldn't base a decision like this on 1/4 mile times.
I would definately get more info from the guy before buying it though. I would hate to have a car like that and not know the exact parts it has because it helps to know for future mods.
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