[YVEYANT]

If you are in it for the long haul, you should consider the two stage. It is a lot more durable, can be wet sanded for a show appearance and will give the car the depth that only a base/clear can give in my opinion. Especially for a black car, the sun is just going to attack that car and the paint. The clear helps protect the paint from the elements.
Spend the extra money and have it done right. How much extra will he charge for the two stage? A gallon of clear is a hundred bucks or less...