Call divert is not the answer,
In answer to the question, yes there are cost effective ways to capture all calls, which can either be relayed to you by text or email, there are a whole bunch of companies that will do this for you in one form or another, I think one even advertises on here, just get the service that suits you and your pocket..
The question should be can you afford NOT to have such a service, the answer is obvious.
I am astounded with all the modern technology available to people today that calls are still missed,
If you fail to implement services to capture all your calls good and bad then you have no to blame but yourself.