I have an old pop up camper box, really old, The kind that looked like a tent, all aluminum, that would make a dandy little dog box if you need a pull behind type, and I would let it go cheap. Its probably 4' wide and 6' long, has the little 8" wheels, needs two new ones at that. I'm just tired of it sitting in the yard. First $75 gets it. Would trade it for a decent dog box as well.