We are trying to implement a script that will automate most of our billing process. However, before we launch it, we'd like to test what happens if the credit card is declined, or otherwise not processed. Does anyone have experience with this? Or know of a way to test it?

Our code pretty much just checks a number of parameters, and then uses nlapiTransformRecord to create a cash sale off of a sales order and sets chargeit to T before saving the record. All of that is working great, and we've successfully billed a few orders. However, we'd like to know what to expect if a credit card doesn't go through before releasing this script into the wild, as it were.