I've thought about this too. I have a collapsible ladder for cleaning my slides so I don't that I don"t have to get on the roof. I could put the ladder where I want the panels to go on the roof, have the DW pass the panels up and I stick it on the roof facing the noon sun, then lock the ladder away.
Someone could go up the rear ladder, walk to the front, cut the cables and climb back down, but then they would need cables and a controller to have a working unit, plus they would be conspicuous during the crime.
While my controller is presently mounted to the back of my suitcase panels, I plan to mount it near the batteries and use Anderson connectors to connect the panel cable to the controller.
While camping in Grand Teton, someone near us left their portable panels out all day without issue for several days.
