5X8(non v-nose)two bikes using pitbull restraints, one generator, one bike ramp, lawn chairs, folding table, ezup, one shelf housing two sets of tire warmers and a milk crate full of tools and spares, two 20L gas jugs, one rear stand and another toolbox.  You have to get clever with the space, everything in ours has a specific place, we are still trying to fab up something to get tires in their as well.  Though we have shoe-horned stuff in nothing touches the bikes.  I am sure it's doable without the pitbulls but it would be a trial in extreme patience.  The stands, cooler, tires and gear bags go in the tow vehicle.  We have pulled this setup with a 4cyl element and a small mazda pickup both with ease.  My buddy and I both would have preferred a 6X12 but the 5X8 is much smaller and easier to both tow and store in the driveway.