The most significant benefit of using Microsoft Teams for your phone needs, is that it helps you unify your communications and productivity channels into a single solution. A further benefit of Microsoft Teams as the foundation for your phone system is that it’s a Cloud-based infrastructure. As with any Cloud-based service, one of the crucial benefits is the ability to access it from anywhere. 

Pricing for using a calling system with Microsoft Teams is relatively minimal. The pricing depends on the system you have set up and the level of Microsoft 365 license you’re using. 

Further Information:

https://www.microsoft.com/en-au/microsoft-teams/voice-calling