Some good ideas. I am heading to The Circuit of the Amaricas in Austin to watch the GP bikes next weekend and will be crashing in my Panel. The air mattress seems like a great idea.

 

I would do the memory foam, the stuff is like a cloud to sleep on.

 

I have a twin size air mattress and 12V air pump in the car. I have not required it yet, but almost a couple of times. The trick is to not over inflate, you really only need a lb or 2 of air. If you do it right you don't have to worry about bouncing things (or people) around.