This year when we traveled cross country I bought a 5,000 BTU window unit. When at campgrounds I would set it in the bottom of the cabin entry door with the edges of the door lined with cut swimming noodles and a 2X4 on edge in the cockpit to support the back. I then applied the sunbrella privacy screen down to the top of the A/C. I plugged it into the outlet in the cave. For sleeping at night with temperatures well above 80 degrees it worked like a champ. It wasn't necessary during the day since we were either on the road or out sightseeing. I am not sure if I would want to use this setup while cruising, but after a few hot sleepless nights it may be something I would consider. For the cost of $150.00 for the A/C at Home Depot it was a great solution for us while traveling and not being able to use the marine A/C while not on the water.