How to make outgoing communication in the office from 1 number?

Question

Telephony

There is an office for 4 managers, incoming communication from clients is made through Wirth. PBX (uiscom) to 1 number, then forwarding to mobile phones of schedule managers.
I want to organize outgoing communication according to the same principle. To account for all calls. So that customers always see 1 number. Even when the manager is not in the office, so that he can make a call from his phone and the system recorded it.
Whis is tired of his lags + the support there is very long. What do you advise?

Answer 1

sip-client on the phone and the system will fix everything, but a minimum stable 3G on the phone is required.