My requirements are that the miniatures be transported safely, without damage or knocking against each other; they should be easily removable from the storage case (which I cannot say for the package they come in); that the storage method be cheap.
Solution: I scrounged a large, flat box (used to hold computer equipment) with a lid, it measured out at 16- inches by 13 inches by 2 inches. I bought a 16-in by 20-in piece of 1/2-in thick artist's foam board, and cut it so it would fit snugly in the box. Just to be on the safe side, I glued the foam board into the bottom of the box with PVA (Elmer's white glue). I arranged all my planes in the box and marked where the mounting plug was, as well as the wheels and the propeller blades. Using a sharp X-acto knife, I cut a "well" in the foam board for the wheels and the propeller (where needed) and punched a hole where the mounting plug goes using a needle-file. With the miniature nestled down in the well, I marked the wings at their furthest point forward and aft, four marks in all. I punched a hole where the markings were (after removing the minis), and inserted a round wooden toothpick in each hole, with a dab of white glue. Trim the length so that the toothpick extends above the wings 1/2 inch or so. Once dry, I simply place the minis in their assigned wells, and hold them in place with small rubber bands tensioned around the toothpicks and over the wings.
The minis are securely held in place by the rubber bands and toothpicks. I can even take the whole box, hold it upside down and shake it, and all the minis stay where they belong. To remove the mini, just pull off the rubber band and pop it out!
The rest of my stuff-- cards, pegs, bases, counters, etc.-- fits nicely into a Plano box as mentioned above already.
The box was free (scrounged). Foam board, toothpicks, rubber bands, and white glue were the only expense. The whole set-up, including the Plano box, cost me under $15 US.
BTW, I have one copy of each mini released so far, plus a few from other makers, and they all fit in the one box with a little room to spare for future releases. I may need to make another box, though, as I'm working on a scratch-built Caquot and Parsival, and would like to aquire a few Gotha bombers as well.