Do you want this car? Is it in good condition for its age? Can you afford it?
If the answer to these questions is yes, then ask yourself another one, do you think you can find another one as good, for less? [anytime soon] If this answer is no, then make an offer on the car. Don't get too stingy about it with a silly offer, but perhaps $2,500 may be enough to make it yours. Worth a try, but be prepared to go to the full asking price in increments if the owner won't budge.