New Product Category

Currently there are only 3 chargeable product categories. Package, refill and DID.
I would like to add SIP Devices as product category so that we can charge customers a minimal monthly fee for adding a SIP Device to their account. Any ideas?

Seems to copy the code from a DID, and make a special entry into the database for the device. Recall there are also switches to deactivate an account. Maybe you can throw that switch in the code to shutter the account when not paid.