I co signed for my son on a Sonata last eyar.Evry time he is a few days late on the payment they call every 2 hours. I have received 13 calls since Decembe 30th. I was out of town but checked Caller ID. I have sent them a letter asking I be put on their do not call list. Anyone had any luck with doing this? There are several threads I found on the net describing their tactics.