Hallo Vince!

 VC> I am considering getting one or more phones for voip and if
 VC> successful kill off the land line.

Check out https://www.linphone.org as they are not only opensource but have 
runtimes available for mobile, tablet and desktop.  Also ports for OS/2, 
Windows and Linux, although the Linux port is probably native and not really a 
port.  ;-)

My best guess is that it is probably the best thing going in VoiP land.  Your 
milage may vary.

Het leven is goed,
Maurice

... Huil niet om mij, ik heb vi.
--- GNU bash, version 5.0.0(1)-release (x86_64-pc-linux-gnu)