An 8x8' Ironman awning, walls, moving blanket flooring, tables, chairs, and an inflatable mattess, and I don't regret a thing.
I have 64 sq/ft of living space, I can stand up, I can detach the awning quickly and drive away leaving it erected. It takes maybe five minutes with help to set up, and maybe 10 to pack it all up. All in price is about 500 bucks, and I don't have a giant box on my roof all the time.