I recently started upgrading my collection storage from cardboard boxes to plastic boxes. Most were underbed storage boxes, long, and flat. Since most of the collection is Roco Minitanks and similar vehicles they don't need a tall box. Many of my cardboard boxes had wooden shelving inside that allowed me to put two layers of models inside one box. With some of the Hot Wheels and Paul Heiser resin kits, the boxes could be pretty heavy. Since the cardboard boxes are in some cases as much as forty years old, I figured this new configuration would have to last the rest of my life. I am in my mid-50's so if these new plastic boxes last forty years, then I may have to do this again, when I am 95!
These are the first few boxes inside one of the sheds. The sheds are eight feet across and ten feet deep. These boxes are 18" X 33" long and about six inches high. I put a blank 3 X 5 card inside each box at the end with the weight sticker to indicate the contents of the box.
I put the windows and the sky lights at the north side of the shed so the boxes would not be subject to direct sunlight.