It sounds like the dealer put a Band-Aid on the problem. You need to remove the oxidation before you can get a good shine.
One method is the
Zep/Red Max Pro Process. It's usually used on older RV's. If your rig came from Arizona it may be a good candidate for the process.
Many cringe at the idea of floor wax on their RV so, use the car/boat wax of your choice after you clean the fiberglass and remove the oxidation.
I'm sure other products work well. This method is effective and inexpensive. There will be labor involved but, any method will involve labor to remove the oxidation.
Try it on a small area before you do the entire RV.
It works well and gives a good shine to our 96 Southwind.
Preparation is the key to a good shine.
