Although it might too "old", the 1:18th World War II German Half Track they made works great. I came across one about 6 years ago in a hobby store on clearance for 5 dollars. Went out to buy some paint, came back with an APC!
I might dig it out and take some pictures, most of my stuff is still in boxes after moving a couple months back. I want to say I was able to put 12 cobra troopers in it and 4 stinger drivers as the crew, two in the driver seats and two in the gunner positions. And It'll fit like 20 ARAH cobra troopers too. Or something close to that, I had 4 of the six packs of troopers stuffed into it. I remember that much.
I need to get off my lazy butt and get around to customizeing that thing with cobra colors.