One Time Phone Numbers
You don’t want some people to disturb you regularly. If you are doing this right, then people around you know that and know you might not pick up if they call without an appointment. But what if it’s an emergency?
Have one time numbers you can give out to people. Each gets a number they can call in a case of emergency. After you pick up (you can identify these numbers by their unique area code) and finish the call, that number no longer works. If that person needs a new one, they can ask for it.