I called the guy too and when he replied with "which car are you calling about" and then when asked if he was a dealer relied "no" I figured his credibility went out the window. He couldn't tell me much about the car other than he buys and sells cars "all the time". RED LIGHT flashing...
Not to say that you can't get a good deal but I'm super cautious especially when buying from guys who "buy and sell all the time" and don't call themselves a dealer. I would go over this one with a fine toothed comb and verify everything on this car.