In order to simulate an AVS response in the demo/test environment, you must first set up your AVS Filters under your Terminal Settings.
Set the first character of the address value to the desired AVS response codes.
For example, setting the address value to "N123 Main St" for a transaction would simulate the AVS response code "N". If the transaction is processed under a terminal that has the "No match" AVS filter checked, the transaction will be declined at Payeezy Gateway due to failed AVS verification based on your settings.
For an API transaction, the address value should be set in the VerificationStr1 attribute of the request.