We have a small inflatable pool to take sitz baths inside with warm water from the solar shower in the roof cargo area, or the stove. (Cunegonde gets used for city stayovers and winter/snow camping as much as temperate outings). If it’s warm or private enough, a solar shower and tarp enclosure hanging from open rear hatch. 

For toilet, a 5 gal bucket with disposable blue plastic bio liners, 5 gal bucket sealing toilet seat lid (they sell these for river rafting outfitters), and a bag of sawdust. Just fits under the bed when bed’s unfolded, bucket goes on rear hitch cargo platform when we don’t want it inside. Essentially an update on ye olde cedar bucket, with no liquid to spill and minimal smell due to sawdust and sealed lid. The used bags can go in camping/RV/marine honey bucket receptacles.