I use a round duffle bag that was a free give-a-way gift for selling Wiel-McClain boilers. It ain't much, but it carries a cleaning kit, up to three pistols in their cases, muffs, and a stapler. I carry my holsters, speed loaders, and paper targets in a 5 gallon bucket that I also use to put my brass in while shooting, and I carry my ammo in a 50 Caliber mil-surp ammo can.
Since I do a lot of Bullseye shooting, I'd like to build a gun cart similar to what the CAS guys use, but mine would be designed for handgun shooting only. I want to build a box that will carry at least 4 guns in their cases and lock, another compartment for ammo, and a third for my cleaning kit, and other accessories. It'll also have a place for my binoculars, and paper targets. I want to build it onto a hand truck so I can wheel it out to the firing line...
I figure a sheet of 3/4" cabinet grade plywood, a light duty hand truck, and whatever hardware I'll need shouldn't run me much over $75.00.....