Price does seem a little too good to be true, however have it checked out. When was the last service, what is due now? What about brakes / rotors? AC filter changed last etc. How is the rubber, alignment shocks etc.
The line I use is " I have learned over time that if a deal sounds to good to be true, it ususally is." Can you honestly tell me the reason why you are selling this car at such a good value?" Watch his eyes, hands, body lanugage and if he squirms or seems like he is not telling the truth, pass on it.