I just want to make sure that I am shopping for the right product. We have a dental office with 1 phone#, but we have a rollover line. Our fax has it's own# which "was" what we called line 3 but as of today a jack was installed just for the fax, we can dial out on all three lines though on our 4 line corded phone systems. I want to buy cordless phones and a new fax. Can't I just plug the fax into it's own jack and just buy a 2-line cordless phone system with (multi-handsets) to use instead of our 4 line corded phones? We do not have 4 trunks coming into phone system. Again, one main line(one number) with a secondary rollover line and separate fax number. Two more things-I am not planning to replace the lab phone (which is equipped to handle 4lines) so can I use the 2 line cordless phones in the office while having a 4 line phone still in use? Last thing-Can anyone tell me if 6.0 ghz would be safe/private enough to use in a health care setting. I cannot have outsiders hearing protected info. Sorry to sound so redundant and clueless, but I just need to confirm I am doing the right thing here. Thanks so much!!