I happen to have a couple of small compartments that are not useful much else over the cab area of my B camper. I installed 2 cigarette lighter outlets and an 110 volt plug in the back of one and a single cigarette outlet in the back of the other, I can mix and match either USB chargers or other charges. Have not needed the second compartment for charging so far but the main compartment works well for charging a laptop and a couple of iPads. on the wall outside the compartment I gave a small shelf with a rail around it, just big enough to put two iPhones on end leaning against the wall. Above the shelf I have a double USB outlet that has a voltmeter between the outlets just to monitor the cabin battery. I also scattered a couple of more cigarette lighter outlets in convenient places around the camper just in case, not used often but nice to have already installed to cut down on cables draped around.
