I started removing fake painted paneling in my new home and have discovered that behind it is thick plywood. It looks pretty sturdy, so I don't think I want to remove it, but I'm wondering how to finish it off when all of the paneling is off. Can it be caulked and painted? Plastered? Wallpapered? I'm trying to go the least expensive route without having ugly walls again. Note: this is not OSB plywood. It looks like wood with a grain. It's kind of rough to the touch though.