I have an Audi keychain and on the back of it, it has one of those things that say drop in any mailbox if found right? Well, there is an address on the back, but since I bought this car used, where will my keys go? Can I get them sent to my address? DO I have to have em registered? BTW, this in an official Audi keychain, it is sqaure with the rings on the front. Later Rob