Hi Marilyn. At this summer's
Fiberglass with Class meet in PEI, one Boler owner painted the inside with roll-on paint from his sign-painting business. It is designed for those vinyl banners and is totally flexible and temperature compliant. He sealed his seams by removing the trim, filling with paintable latex caulk and smoothing it prior to
painting. It looked super! Me,I just scrubbed the walls and ceiling with Tilex and then polished with Armor All and the surface was rejuvenated.
Good Luck...Alistair