It is unlikely that each cylinder is 210 psi, rather, around that. Assuming the range is correct, it is not unlikely at all.
A leak down test, as I recall reading, is a better barometer of engine health over a psi test in each cylinder.
What is the mileage of the car, price he is asking, and has all the service been done? Yes, he may have a dedicated mechanic, but that does not mean he has paid for all service...timing belt, water pump etc...
Also, is it in snap-ring range?
Congrats on your find. I hope it works out for you...