I use D rings hanging from the "rafters" for the hoses, also use an Evo Flex. Use D rings with straps to hold two small tables upright against the rear wall. Use bins for anything wet-aerosol cans, cleaners rags etc, another for sewer fittings, all in the pass thru.
Since I have gen prep in the foreword bay, I put a wire shelf in the pass-thru on the forward wall, miscellaneous stuff goes on it-leaf blower, elect. adapters, triangle reflectors, flags in small bins extra hoses. Bins fit underneath it.
DEF goes in the bed of the truck, along with a grease gun, grease, seals, bearings in a tool bag. The bag goes in the front of the bed along with my 2K watt Yamaha, & a toolbox with the impact wrench, & other stuff to change tires with & another toolbox with tools. Cabled & locked to the bed with a tonneau cover when not towing.
Front bay holds the collapsible ladder, trailer tool box (pex fittings & tools, fuses, wire, sealants), bicycle tool box, viair compressor. Outdoor mat satellite dish.