Same here . never answer an unknown number. If its important they 'll leave a message and I'll decide after that
This is what I do as well. Then I block the number if they don't leave a message. Doesn't stop them forever but it shuts the down that attempt.
I don't do business over the phone and I if I get an email from someone claiming to be someone I do business with. I take a look at their email address. Their email address will tell you a lot.
