This is a little LED light that goes on when the door is opened (there is a second piece that is on the door, which is a magnet). A mere buck!
Because there are times when we leave the door open, I fashioned a magnet-on-a-ribbon that allows us to keep the door open but have the light off.
Also in these pics you can see the magnet stip from IKEA (also I think about a buck) - this strip couldn't fit any more perfectly on the side of the cabinet. Almost like it was made for this space. Affixed with double-stick foam tape.
Also from the dollar store (Dollar Tree) are these metallic windshield shades.
They affix with suction cups and cover the majority of the bubble windows - this will keep the camper cooler on hot sunny days.