Hi, I can help. Hosted Subscription based RADIUS billing system. Typical setup time for purchasing a billing system, is 2-3 months time frame. I have comparision chart of the different billing manufacturers and their pitfalls in this industry. If you have a Cisco I set up a test route with our RADIUS server in little as a day running prepaid and postpaid traffic. Out of pocket is you providing a TFTP Server for voice prompts if you are doing prepaid. I have free setup and free traffic authentication till November 10th which is our current special.
let me know if you want more info.