It's not that hard to do. The only required thing you have to do is rerecord your voice greeting, and the rest is up to you. While the rest sounds like a lot, it isn't, and you'll get used to it after a while. Threats may not necessarily stop the issue as I threatened to take this to the police with my friend, and that made him do it more. Of course, it depends on the situation. In my case, it was prank calling, and threats just don't go anywhere. If it's an angry ex or equivalent, then maybe, but I think my system is pretty good at getting people to stop talking to you.
