Hello, I am an advanced FusionPBX user and I have already done an integration with FusionPBX and Kamailio which is being used in production by a number of companies for nearly 1 year now. If you are doing multi-tenant you also need to remember that you need to be able to synchronize the tenants in Fusionpbx with Kamailio and all this we have already implemented. I am offering it at the discounted price of $750 + Freelancer fees which comes to $789. Regards, Errol