Phone Line

Oh, and if you can recommend a cheap service too. Is it just Verizon and TW? Or are there other options?

Vonage has a little-advertised cheaper plan.
Works out to something like $26/month after all taxes and fees, total, for 500 minutes.

There's also RCN, but phone may not be available without cable.

If they can't use your mobile (i.e., program the intercom system to dial a phone number), you're probably limited to plain-old copper wire service, which (I'm pretty sure) Vonage and TWC don't resell.

I've heard that some buildings take over the copper wires (if you don't want to get plain-old telephone service) and route the intercom through that, meaning you'd just need to get any old phone to receive buzzes.

yeah IP phones wont work... it's probably twisted pair. get a cheap line from verizon or rcn(if you can)

typically there is a house carrier already wired up right to the jack in your apt - perhaps Vzn. Had to do it in my bldg. If they cld only get Fios in the house i'd be glad.

I don't understand why they can't call a cell?