When my friend Ziv was looking to buy a portable shower for his jeep, I suggested building one for him. To be honest I has no idea how complicated it would be and how much struggle it would take to squeeze all the features I offered.
The tank part was easy, welding a Geberit pipe and some covers. The difficult part was installing an electric pump, two faucets, and plenty of cupper tubing in small space, which could easily be extended, but I wanted to keep it small and serviceable.
To make a very long story short, it works and delivers sun-warmed water.
The pictures are not showing the side 12V water protected socket and the hand held shower spiral hose, which connects to the tank, and utilizes the pump.