When we went camping near MIS last year, the campground did not have shower facilities. Les's brother bought one of those two room tent showers and an on-demand hot water heater. It's propane and you just hook up a water hose to it. That thing worked great! We had people taking showers all day, there was 6 in our group alone needing showers and then we let others camping around us use it,too.
I don't know the brand on his but I do know he bought it new on ebay, same with the tent shower.