I am looking to setup voip from our main office and connect in remote offices via the internet. Can I set this up so that remote users could call local pots numbers on their end and make calls to our local pots area, which would be long distance from them, then also long distance through a voip provider out of the main office on a $ per minute line. and dial extensions within the company anywhere.
Yeah, you can do all that - probably without too much difficulty.
Most of the information you need is at:
and, particularly, at: