This is a Barbie motorhome made of a hard yet thin plastic, and it's softer fixings. Have some sense, don't do this to a bus that's in good shape, them's worth something as they are. Mine has been well loved and the body is cracked in several places. The shower door is warped, and there are other problems that would only make it attractive to a three year old and not a collector.
All the innards were removed and I took the hose to the bus, thirty yeas of dirt and dust bunnies came out. After drying I did a test patch of Krylon Fusion and regular Krylon, both stuck. I tested one of the beds and the regular Krylon stuck to that too. I don't know if I'm going to finish priming in grey (I'm out of Fusion) or just use the non Krylon black we have. BUT first the stickers have to come off.
The not exactly easiest but worked quite well way of getting the stickers off involved a scrub brush and water. I lay a wet rag over a patch of stickers to get them as wet as possible then used the brush to take most of it off. There's still some residue but I'm letting the bus and that dry then I'll wash it again. If there's anything left I'll try Magic Eraser and/or rubbing alcohol.