I know this is possible, but how hard would this be to do, for a novice?

I have a small office. 3 lines, one pots, 2 voip (skyp & vonage).

I know I would need to have a multi port FXO/FXS Card to support the POTS line and Vonage.

I would then like to have different #'s go through Different lines using the cheapest line for the call…all except e911 services that would have to go through the POTS line, and the caller id to read the same no matter what line (if possible)

I’m new to this and searching has brought up some good voip/sip phones but am looking for recommendations on a cordless phone that has POE.

I would also like to know all calls placed, to what number for how long (billing my clients), I assume this can be done via SNMP or other means?

Thank you for your input.