I have multiple telephone services all of which serves a purpose. This is in addition to my [cellular] Number which I pay on an annual basis.
Callcentric
Callcentric handles my [international] Numbers, and my [voicemail] Number. The international numbers are there to make it easier for people in other countries to reach me. Each international number has a respective .vcf file which can be found on my Contact site. The voicemail number is intended to provide a number for the domain registrars. Providing my regular telephone number just leaves me exposed in getting a lot of scam calls for website design.
Line 2
I had Line 2 a couple of years ago, and they had some significant problems with their system that left me to cancel them. With that said, I am trying them again. In addition to providing VOIP services, they also support faxing to the number. A fax will call the number. The system will the listen for a fax tone. If it hears it, the system will collect the fax, and send it to me. If the system does not hear a fax tone, it will then ring the phone. This will also eliminate the need to have to use a separate service for faxes.
Ooma
I have Ooma as a second phone line in case I would need to have a second phone number. This is especially the case since my old iPhone 12 Pro expired, and I had to move my international numbers to my primary phone. If for some reason, I can’t use my primary phone, or if I wanted to call myself for whatever the reason – I will then use the Ooma service.