Much like David, in the bay next to the water bay, where the water pump is located, I keep three plastic bins purchased at WalMart, that have snap on covers. One contains all things nasty. My Rhino Flex hose, fittings, end caps, 15 foot extension, spare fittings, and the water hose I use for the black water tank flush. The container is about 36 inches long and 12 inches deep. I also have a small container that has a supply of latex gloves that I store on top of the large container. Next to it are two 36 x 7 inch bins that have snap on covers. One has wheels and contains all fresh water hose and the portable Water Stick water softener. The third one stores on top of the one on wheels and has all of my "fresh water" related hose needed to put the water softener in line, fittings, and quick disconnects.
When we arrive at a campground, its easy to remove all three bins, take the covers off, snap on some latex gloves, and proceed to set up the water bay. Same when we break camp, haul out the three bins, and put everything away as its disconnected.
I have one of those built in hose compartments, but I have never used it. If anyone has a good use for it, I'd be interested in any ideas.
Stan