build or restore

I have a shot at buying a tear drop that needs some work for 500 bucks ( it has 2 batteries and an inverter that comes with)
I originally wanted to build one but it would probably end up like the one i could buy.
all i am wondering is what to use to reskin the camper or if I even have to reskin? can I just seal it up with fiberglass resin or would I have to use the cloth with the resin
what is the stuff they put on the modern campers the white stuff and is it available
I originally wanted to build one but it would probably end up like the one i could buy.
all i am wondering is what to use to reskin the camper or if I even have to reskin? can I just seal it up with fiberglass resin or would I have to use the cloth with the resin
what is the stuff they put on the modern campers the white stuff and is it available