The short answer is any ebay key will not work on the xfire. Hardware stores cannot cut these keys and would probably not have the blank key to begin with. But even if you can find a place to cut a key from Ebay,it will only open the door but will not start the engine or lock/unlock the doors remotely. Members here have paid anywhere from $75 to $140 from their dealers so it is not that expensive. What you have been quoted as $400 probably includes "programming" which you can do yourself in 20 seconds by following the instructions in one of the threads.....use the search button to find it. Hope this helps.