I want to hook up shower and I am wondering if can I hook it up so that the
pump just has an on/off switch and use one of those kitchen sink hand held
dish sprayers that just cuts off the water when you let go of the handle.  I
am wondering if a shurflow or similar small RV pump can run even when the
water flow is turned off at the handle or does that cause huge pressure
build up and damage.  And is there a pump that could be used like this?
Or maybe a better suggestion.

Thanks