I bought a dozen plastic "Spacemaker" storage boxes from Wal-Mart for 33 cents each on sale. (Normally they're 66 cents—still cheap!) These are 5" x 8" x 2.5" translucent boxes with hinged lids. I used them to store things like "water accessories" (hose washers, Y's, nozzles, etc.), 12V electrical fuses and bulbs, camcorder accessories and so on.
I labeled each box (and pretty much everything else) with the Casio KL-7000 labeler I carry with me in Gertie. (I picked this up as a half-price refurbished unit at the Casio Factory Outlet in Lancaster, PA.) It's similar to the widely sold Brother P-Touch labelers; I just happened to be able to get an exceptionally good deal on the Casio. I also used it to make reminder labels for various places on the coach, such as "TURN OFF WATER PUMP BEFORE CONNECTING" above the city water inlet and "Clearance: 11 feet/Weight: 5 tons" above the driver's-side visor.
The previous owners had pretty much filled Gertie's wardrobe with plastic Rubbermaid storage drawers, in addition to three shallow full-width wooden drawers that may have been standard equipment (I don't know). This prevents hanging up anything, but I frankly don't care if my clothes are a bit wrinkled when I'm traveling—and the Rubbermaid drawers make far more efficient use of the wardrobe's space.
I also used large plastic Rubbermaid-type drawers in the under-couch storage lockers (the ones accessible from outside the coach) to organize the contents. All the sewer fittings and my heavy Bluettes gloves, for example, are segregated in one, so they don't slide around the compartment contaminating other stuff. All the spare belts, hoses, bulbs, fuses, emergency repair tape and patches are in another one that's labeled "Spares & Repairs."
The wardrobe closet originally came with a hanger bar...and that was it. Because that's an inefficient way to store clothes, I filled the entire wardrobe with plastic storage drawers purchased at Bed, Bath & Beyond. (I don't care if my clothes pick up a few wrinkles from sitting folded in a drawer—I'm not out to impress anybody with my sartorial elegance!)
On the left I used Iris "Hard Tops" drawers, which are 22" x 15 11/16" x 25 7/8" and come in a stack three drawers high. I bought two stacks, disassembled and recombined them as a five-drawer unit (six drawers would have been too high). To keep the stack of drawers from sliding around while I'm underway, I used 1/2" half-round molding nailed to the floor of the wardrobe.
On the right I used seven Iris 2-gallon "stacks up" individual drawers, which are 8 3/8" x 15 3/8" x 5 3/4". I screwed every other unit, including the top and bottom ones, to the back wall of the wardrobe to keep them from moving. In between the two columns of drawers I slipped the extra leaf for the table. I rarely use it, since it's only needed when I have more than two people sitting down to a meal, but it's nice to have.
I noticed that there were a few inches of space between the wardrobe doors (when closed) and the fronts of the various drawers. So I bought eight wire basket/shelves from Wal-Mart (Rubbermaid "Wrap Rack," part number 55113), each one about 4" x 10" x 2" deep, and screw-mounted them to the insides of the doors. This gained me quite a bit of storage space that would otherwise have been unused. I stuffed them with underwear, sleepwear, socks and other oddments.
I also added wire shelves and baskets of various sizes in the rear upper storage cabinets, in the kitchen cabinets, and above the medicine chest in the bathroom. My strategy was this: whenever I saw unused space—for example, above the contents of a cabinet—I added a wire shelf. We're so used to ignoring empty space in closets and cupboards that we don't even see it most of the time, but if you really look for it, you'll be amazed at how much there is!
It bugged me that the wardrobe interior was so dim...it was hard to see what I was doing when I opened up those doors. So I added a slimline fluorescent fixture on the ceiling right outside the wardrobe. What a difference! Now the wardrobe interior is bright and it's easy to see what I'm looking for.
Because I couldn't get access to the area above the ceiling, the new light's wiring had to be run across the ceiling from the kitchen's incandescent ceiling light. Fortunately, I was able to conceal all but four inches by running it inside the air conditioner housing, which is conveniently close to both the kitchen light and the new light fixture.
I was bothered by the fact that when I was sitting on the couch, there was no storage within convenient reach. So I bought a small three-drawer Rubbermaid-type storage unit from Wal-Mart and used it for stationery supplies. It sits on the couch to my right, where I can easily reach it when I'm working at my Jotto Desk (which is floor-mounted just forward of the table). Drawing and writing implements go in the top drawer, paper in the middle drawer, and cutting and measuring implements in the bottom drawer.
To prevent the stationery cabinet drawers from sliding open while I'm traveling, I applied small rectangles of 3M Dual Lock (similar to Velcro but with much more holding power) to the rear edges of the drawers and the cabinet interior. These secure the drawers, but permit them to be pulled out easily.
In fact, I've used Dual Lock extensively in Gertie. This extremely useful fastener material isn't well known, so I've created an "All about Dual Lock" page that describes it and how to work with it in detail. Check it out!
This is almost too obvious to mention, but I bought a bunch of Rubbermaid modular plastic drawer organizers at Wal-Mart—small bins in various sizes that hook together, so you have considerable flexibility. I used them in my "Tools" and "Electronic tools" drawers to organize the random clutter that filled them. I hate random clutter! And I never could find what I wanted without a lot of pawing around. Now I can.
The bathroom had no storage aside from the small medicine cabinet. I changed that in a hurry! See the Bathroom page for details and photos.
I added a wonderfully handy multi-pouched storage unit to the back of my passenger's seat. See the Cab page for details and photos.
The bulky Lazy Daze-installed bookrack wasn't very practical, so I replaced it with transparent plastic wall pockets.
I found several ways to optimize the storage space in the kitchen cupboards.
Upside-down shelf space
Gertie has eye-level storage cabinets above the couches, running around three sides of the rear lounge. I used the undersides of these cabinets as shelf space by mounting various things there. For starters, I put a "Pop-A-Tissue" holder from Camping World under the cabinet near the stove. This holds a box of Kleenex tissues where I can easily reach up and grab one while sitting on that side of the couch.
I also mounted my trusty Maha battery charger under the same cabinet near the rear of the coach. Batteries don't care whether they are charged right side up or upside down, and this location puts them at a convenient level—and makes use of otherwise wasted space!
The biggest storage space improvement I made was one of the last: I added a "sideboard" in place of one couch, gaining 15 cubic feet of storage and 12 square feet of work surface—vital for a fulltimer who's running a business on the road!
This modification (which, by the way, is completely reversible) isn't for everyone, but it was a crucial factor in my being able to live full-time in a 22' motorhome. You can find complete information about how I did it on the Sideboard page.