I know some use other means and I probably will too when I get around to fabricating something, but my sewer hose goes in the bumper. No issues with rusting anywhere. I have had to replace one hose due to a pin hole from abrasion either in the bumper enclosure or use.
For my fresh water equipment I use one tote; for the black tank flush hose, fittings, caps, gloves etc. I use a 2nd tote. Another tote carries misc. like x chocks and wrenches, an extension cord, some spare magnetic mount motion detecting lights, flashlight and other stuff I can't remember. The last tote is smaller with various kinds of hardware; Roberts screws, speednuts of various sizes and types, Nyla lock nuts of different sizes, various size/type screws, nuts, bolts etc. It also has all kinds of electrical connectors, heat shrink connectors, a roll of "extreme" tape etc. My 12vdc fuses stay in the trailer with some other "stuff". Tote size is determined by what goes in it. I have guestimated wrong at times and those "mistakes" have been utilized for some other purpose. Buy them at Walmart, Target, Home Depot, Lowes and sometimes Dollar Store depending on what you need and when.
