What is the best way to organize IP-telephony in the office (Asterisk + FreePBX)?

Question

Asterisk

Good day, dear toasts :)
Tell me please, how is it better to organize telephony in the office? The office will have a maximum of 15 people.
I want to install a server and install Asterisk+FreePBX with a USB GSM modem on it, for example Huawei E173, so that all telephony is "at hand", and not somewhere in Kolyma, the provider has budget restrictions.
What is the best way to organize all this and what pitfalls can I encounter? What IP phones are better to take (budget, but high-quality options)? And in the future, it is planned to use not 1 number, but 3 numbers connected to one telephony, how should this moment be taken into account when planning?
I'm waiting for your advice! Thank you in advance!

Answer 1

I would do = Asterisk + FreePBX + SIP multiphone, if you need a "city" phone, you can connect to the same multiphone. From the start there are 2 channels + you can expand by calling support.
PS: E173 calls, it doesn't even ring badly, and it also freezes periodically.

Answer 2

What is your question?
Huawei E173 - it's a modem, it can't make calls. See full-fledged GSM gateways .
In general, Megafon-Multifon. Do you want to drive vulture, you want to Simka.