One last item we found during that trip at the flea market was the Batboat from the Lego Batman playset #7780. If you are familiar with Lego Batman you know just how rare and expensive this is. We got it for only $10!
It is almost complete. Actually after downloading the manual online (thank you Internet) I noticed that it is missing one small piece, the one that holds one of the boat's wings. Thankfully I found that very piece on the Lego web site, available for purchase for only 17 cents!
This is a very cool 10 inch hydrofoil Batboat that features pivoting rotors and a small detachable boat in the back.