I'm opening a satellite office with an 8 line key system. Can I use an MVP810 on either side so the main office can transfer calls to the satelite office? Can I access the main line pool for outgoing calls, possibly hooking up a fax to the unit?

The MVP810 can extend 8 analog lines and allows faxing. Typically key system CO ports will have an FXS interface and PBX analog station ports FXO, so the VOIP would need to be configured accordingly. If you have 8 analog extension ports at the KTS side attached to the mvp810, and 8 analog phones or fax machines connected to the satelite mvp810, you would dedicate one PBX extension to each channel on the satellite side. You would setup auto call from channel 1 to channel 1 at the other end. So the PBX extension plugged into channel 1 at the satellite, is the extension of the phone plugged into channel 1 at the satellite. A call comes into the main KTS, and you just transfer it to the extension that is plugged into the mvp810 that corresponds to the channel at the satellite.