Here is a YouTube video demonstrating very nice, customizable miniatures storage system, for your home. I do not know if he made the pull-out trays himself, or if they came with the unit. I do know that with some basic crafting skills, and some basic wood-cutting skills (table-saw techniques), a person could build those trays.
Years ago, at my local Good Will Store, I found some similar shelving units. I cut some L-bracket aluminum, screwing them into the shelving unit. Then I cut a sheet of thin plywood to size, sliding them onto the L-bracket racks. Mine will tip and fall, if I am careless; mine do not have sides, front or back, they are just flat trays. His setup is much nicer, and I am tempted to add sides, front and back, to mine, after seeing his setup.
My setup has slots in it, but the slots are too thin to insert plywood into. I don't have a router to widen them, so I went with aluminum L-brackets which work almost as good. If I had used thinner plywood, it would have been too weak, flexing under the weight of my miniatures. My system requires me to carefully support each tray as I slide them in/out, so as not to dump them onto the floor. Adding sides, and a front/back would be much safer. I might need to do that…
Side note: The plywood sheets can be left bare, covered with felt or fabric (see vinyl, below), painted, or covered with kitchen shelf liner, if desired. I covered some of my trays with left-over vinyl faux leather from my old Ping Pong Table (covered with vinyl after the surface became hashed; used it for RPG and miniatures gaming). The vinyl was gently stretched and wrapped over the edges, then stapled on the bottom. It's overkill, but I had it, so I used it.
Anyway, thought it worth sharing. Cheers!