For the home telephone, I will use a Wifi phone that I currently have This phone connects to my provider using SIP credentials, and therefore – accessible anywhere I have a Wifi connection. There will be a similar setup if I was to have this building. The only difference is the SIP line will connect directly with a PBX server rather than the provider. This is to support the telephone lines from the elevator, and the voicemail/fax line for the system.
If I was to have a significant other, and if she was interested, I will acquire a Wifi phone so she can also have a home line. This will eliminate the need to have a direct “house” IVR service to direct callers to the correct person (such as press 1 for Frank, press to for significant other, and so on). Obviously, this is not a requirement as most people rely on cellular phones, and with most people having smart phones, they can install a SIP app on the phone if they want one phone for multiple numbers.