33gal freshwater, about how long will it last?

With our previous camper, about three days. That factored in 4-5 "navy showers" and dish washing. Obviously, if you hike in dusty or muddy conditions, you may run out faster.

Our gray water tank was smaller than the fresh water tank, so it was more of a problem than the fresh water tank capacity. I would stop up the little tub and scoop out the shower water into the toilet to save gray water tank space.