Shower Pan Bathroom
Just a thought. I used a 2' x 4' shower base for the bathroom, set the rv potty on the back (cut a second hole in the base for output) and framed up the shower base. Found a small corner sink at RV Parts Supply Store and added a shower curtain that pulls across the door. Towels stay on wall behind the shower curtain and you can do all three "S"s in the same space! The rv potty drains directly into the black water tank below (there is about 18" between the floor and the top of the tank) and the shower water drains over to the gray water tank with a trap under the floor. The faucet for the sink has a shower adapter on it with a hand held wand that also mounts to the wall. The interior walls are all FRP. Added a mirror above the sink (12" x 12" mirror tile worked great). Just close the top on the potty and you have a shower seat!
'99 Freightliner FL70 with 22' Box, Cummins 5.9, Allison 6 speed, Liftgate Toyhauler, with 28' Enclosed Car Hauler.