Billing system for Asterisk

Hi. I’m looking for good billing system for Asterisk. What is better? something commerce or opensource ? What did you prefere ?. It should be have DID management, voucher etc, and admin and user web GUI management. Please for help. Thank’s. Bye

There are many reports that this is a good free billing system

I have not used this one as we created our own one so we could customize it exactly how we wanted it.

But take a look at this one, it has an active community for it so support shouldn’t be a problem.