We put a longer hose on the shower hand held and feed it out the bathroom window.
You could get another storage compartment door from Casita and install it where they put the outside shower. This would give you outside access to the under seat storage area in the Spirit for your hose and stuff, makes setting up more convenient.
On the 13' Patriot Deluxe,16 & 17' Liberty Deluxe this would access the area under the kitchen, and with Three pieces of wood you could fashion a shelf/compartment there.
I did this on our 13' and 17' Casitas. Heres pic's of the 13' and 17'.
On the 13' I relocated the electrical
On the 17' I also added a convenience light