I recently opened a web store and accept credit cards through Authorize.net. I'm finding that most CC are declined because of AVS mismatch. Not because of an actual difference but because the bank doesn't support AVS:
What do people do in order to allow these foreign customers to use their credit cards but not open yourself up to fraudulent activity?[billmes] => The transaction resulted in an AVS mismatch. The address provided does not match billing address of cardholder. (AuthCode: 025772) (TransID: 5264999387)
[avsmes] => The U.S. card issuing bank does not support AVS