I received a rather large order on one of my web sites tonight through my SecurePay gateway which had an AVS response code of "U".. "Address information unavailable. Returned if non-US. AVS is not available or if the AVS in a U.S. bank is not functioning properly." What do you guys suggest? Phone verification isn't even reliable these days. I've had an instance where a fraudster used his own cell phone number and answered, told me he was the card holder and that he placed the order. 10 days later, CHARGEBACK!..
Trust your guts. If you feel uneasy about the deal, just refund it. Incidentally which country is the credit card from and does it match the email address, ip or mailing address provided ?