We seek assistance from knowledgeable person(s) that can help us build a simple PBX — a PBX wherein we can have a maximum of 25 extensions that will dial out to SIP URIs rather than to PSTNs.
We are working with the Center for Disease Control (CDCMex)Mexico, and are non-profit, and will work well with the person assigned to this project.
Did you look at official FreePBX Support ?