Our extra key sets were also made at an Ace Hardware Store. The only key we keep hidden outside the coach is one that I deliberately had mismade. The key is "cut long", and if it's inserted in the lock normally, it will not work. Withdrawn just right, it works perfectly. The other spares are tucked away inside the coach. Our toad requires a chipped key to start, so the hidden outside key for that is a dummy with no chip. It will unlock the doors, but that's all. A spare chipped key is hidden inside.