The reason the "pro shops" can do that is they are "pros" and know how much they put on each part equally.And a high metallica paint is even harder to get a steady coat across panels that are seperated.It helps to go from one to the other while on the car.As needsaseto said being a novice go with the same paint through out.Thats what my intentions are to use the single stage thru out the car and then clear everything if i dont 2 stage it all.