Recently, I purchased a couple of remotes for extras.  Thought was that I could get them programmed at the dealer.  My car is a Volvo and I have learned that to get the remote programmed, one must have the original package that has the "long" and "short" codes.  These codes are entered in the technician's computer while he has your vehicle attached with a digital cable.  Obviously, there is no original package for these used remotes, so they are worthless.

Other manfacturers, both foreign and domestic, may have ways to program remotes without this information, and that can be clarified at the dealer.   I talked with the counter at the Volvo dealer and was given different information that when I showed up asking for the used remotes to be programmed.

This is certainly a product for a buyer to be sure of what he is buying.  You  may end up with something that is worthless (or sell it to the unsuspecting or unaware).