Has anybody done this?

 

I'm completely at a loss, having tinkered very little with Asterisk, and giving up on that, I wonder if there's any help to be found on FreeSwitch?

Anybody that can give pointers to a good step-by-step instruction?

 

I want to have it handle my two sip-phones (siemens dect ip and spa 901), and handle a sip account at my provider.

Of course transferring calls between the two, as well as group calls would be a nice benefit.