Fios was just made availble in my street. I found out because a door salesman came by and informed me. His price was lower than what I would get if I signed up online so I ordered with him. I did not know that I had two choices for phone server, Freedom Essentials and Digital Voice. He signed me up for Freeodm Essentials but I've read that it goes over traditional telephone so there is more tax than there is for Digital Voice since its VOIP. So I was wondering, can I change to Digital Voice after the installtion is done and not affect my contract/price agreement?