My short experience has been copious use of plastic bins (stackable, when appropriate). I store everything from protein bars and K-Cups to air compressor hose and tire accessories, water hoses, sewer hoses, snacks behind the driver seat, on top of a bin with my rai/hiking boots, etc.. There is a bin for almost everything. There are tall bins under the kitchen sink for tall cleaning products and spares, and small open bins under the bathroom sink for the same. On top of the bathroom counter is a bin with all of the dauily stuff liquid soaps, disinfectant cleaner, toothpaste, body lotion, etc.). I found Dycem non-skid material great for keeping things from sliding on the counters, so the Keurig, toaster, and daily use stuff stays on the counters during travel.
The current unit has very tiny drawers in the bedroom and a shallow, but nice sized closet. I put two shelves on one side of the closet where, I keep the bedspread and blanket on the bottom and I can stack two bins on each shelf for an extra towel, sheets, and clothing.