Our trailer came with lift-off plywood covers for the storage under the dinette seating. I think this is the typical way this is done at the factory. It's a real you-know-what to lift off the cushion and manhandle the plywood out and off to the side just to get at something inside. Ours also had a couple of horizontal braces from side to side which got in the way.
My solution was to rebuild the whole flippin' thing and install a piano hinge. I made the lid smaller so it would clear the back cushion (now held in place by Velcro), blinds on one end and counter at the other. I glued down 1/2" foam as well to hold the cushion in place. This works great!
