[Rick V]

Keep a small compressor that can be plugged into the cig lighter to finish the tire inflation. a can of fix-a-flat won't pump your tire up very far. And make sure to tell the folks at the tire shop that you put fix-a-flat in the tire. as a wrench (who doesn't do tire work anymore Thank god) I can tell you that you are risking your life my not passing that info on. It is nasty stuff to work with.
I like your idea and am going to do the same thing to the wife Boxster today.