That's a tough question to answer. I have a hummingbird. The roof is one piece fiberglass. I have used a few brand's of wash & wax,the one I like is rv gel gloss wash & wax ( about $20.00 a gallon from camping world ). I think you should give the folks year,make and model of your rv to get some better answers. I'm an old retired gm partsman and that would be the first thing I would ask you. Looking forward to the answers you get.
1984 gmc k1500 4x4 s/w/b. s/b 350,700r4,373 diff,.restored and upgraded( retired - sold). 2022 Chevy Z-71 Trail Boss 4x4 crew cab s/w/b 6.2 gas a/t. 2018 hummingbird Baja 16mrb,Yamaha ef2400ishc inverter.