If you do base / clear make sure to get the same coats of clear on all the body panels (if they are not all fitted on the car.) I painted my hood off the car and it has more clear on it than the fenders, and in the right lighting conditions you can see the extra clear makes the hood look slightly darker than the fender. I'm a novice at painting, so I will let others comment on the recommended number of coats of clear. I think three coats would be the minimum because you will want to sand and buff the clear.