Contact the dealer where the paperwork originated for the cpo issue. Their position that the paperwork was "never completed" is hearsay. As far as the previous owner and you are concerned it was valid throughout his and your ownership periods. Unless the dealer can prove the paperwork you hold is a forgery, they are represented by it and should be obligated to honor it. Act like you are getting alawyer and negotiate, negotiate, negotiate, you get what you negotiate for in life not what you expect or think you deserve. At the very least the dealer should be glad to give you a big discount on an extended warranty unless he is hiding something about the vehicles history. Stand up to them, walk a picket line in front of their dealership for a day if you have to, I guarantee one lost sale is worth way more than them making you a happy BMW owner.

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Well I guess this ain't gonna be easy.......