Need a second line.

We have two phone lines; one for me and one for my wife. I switched my line over to VOIPo and am very satisfied. My wife is interested in doing the same. She wants a full service line, like mine, not just a virtual number. She wants full control of all the features that will only affect her phone.

I have a Grandstream HT702 with imputs for Line 1 and Line 2. Can we get a full-service second line with a ported number (from Century Link) to work with the Grandstream that we have? Or do we need a second ATA?

I don’t know anything about settings or ports or other technical stuff. I’m hoping I can just plug the new full-service line into the Grandstream like I did the first time.

If this is possible, anyone know what is the cost of another full service line.

Notes: currently ATA plugged into Linksys E3000; have Comcast cable internet