[Cool Hand Lurker]

You can get a roll of industrial heat shrink film for about $200 that will do at least six cars. That will keep junk off your car for several trips or you can share it with other guys in your club. This is the stuff that is used to cover boats when they get delivered from the factory to the dealer. When you shrink it, nothing will flap.
Here is one source: uline.com but there are others.