One other thing to watch for when backing is the crown of the road. While backing into a campsite with a large tree at the entrance, I was sure I had cleared the tree but didn't allow for the side to side tip of the trailer due to the crown. A long scape of an upper limb of the tree tore the rubber roof right at the edge of the trailer. I, nor my spotter, realized we had hit until the next day. She says to me, "What's that on top of the trailer?" After an emergency patch of about 6 feet of rubber roof, all was secure until we got a new roof installed. Surprisingly, there was no frame or plywood damage: just a long tear in the rubber.