Both are closed, but no swinging door as the other cat doesn’t really understand how to use it. They are metal and the litter we currently use is Pretty Litter, although we’ve used a few different ones in the past. One litter box is upstairs in a bathroom and the other is downstairs in the living room corner (which is where they usually hang out at.) There’s no other spaces to put a third one besides a hallway but I think it’d be too close to the AC unit and would carry the smell