There's my primary rollaway (which has been supplemented by old kitchen cabinets until I decide to upgrade to a wider, deeper toolbox) that has a huge and complete assortment of tools, essentially two each of all the basic items. These are all the Proto, Wright, S-K, Williams, Channelock, Blackhawk, etc. As well as the basic stuff, these include all the wrench sets other than combination wrenches, all the 3/4"-drive stuff, the pullers, the engine assembly tools, the really small tools, the special-purpose tools, etc. I keep them clean, mostly using them for assembly work; cleanliness is essential when working with engines, especially diesel engines and fuel injection equipment as I enjoy doing. The absence of peeling chrome and other FOD is critical. These tools also constitute my "arsenal" of USA-made professional tools just in case World War Three engulfs the world, or Stanley and Danaher finally assimilate every tool brand in America and send production to Nigeria.
Then there's a secondary rollaway, with only the most basic stuff. You know, 10-19mm and 3/8-3/4. This one goes out into the driveway, maybe gets used for disassembly of filthy old parts for rebuilding, and contains all the items that are appropriate for loaning out to friends and neighbors. These are all the third-tier (behind the two primary sets that stay in the garage) tools, mostly Danaher stuff including Allen, K-D, and Craftsman. These get used the hardest but I don't feel bad if I break or lose something from here. This contains the stuff that a professional technician would keep on their service cart.
Then there's the field box - 1/4", 3/8" and 1/2"-drive metric socket sets with ratchets, extensions, and breaker bars, two full sets of combination wrenches from 8mm-19mm, slip joint pliers, needle nose pliers, water pump pliers, a 6-in-1 screwdriver, ph1 and ph2 screwdrivers, a metric hex bit set, a torx bit set, a tiny little cheap multimeter, a prybar, a 16oz. ball pein hammer, and a flashlight. This currently lives in the trunk of my old diesel car that has nearly 500,000 miles on it. I changed the torque converter in this particular car in a storage unit parking space using only these tools. Brands represented in here include Allen, Craftsman, Jensen, Pittsburgh, and a couple others. This box and these tools are actually my favorites, there are some good stories tied to them and they have really enabled me to help myself in some situations that otherwise would have really sucked. The box itself is an ancient, rusty, warped, bent, and dented Vermont American 18" hip-roof box with one removable tray that I salvaged from my friend's recycle bin. It is packed to the gills with these items. I'd like to assemble some smaller field boxes, one for each car in the fleet, with sizes specific to the individual car.