While I was a Mormon and did not have my life or mind together, I went on a mission as a teenager. I went to the California Oakland Mission. The best way to stop them is to 1) If you have a gate, keep it closed and locked. This will stop people that will come to your door as a cover to scout out your home for a future robbery. Have a big dog (always worked with me, hahahaha) and put out a sign stating that fact.

2) Don’t open the door…period.
Tell them that you worship satan and your coven is looking for a volunteer to sacrifice…come on in!

It’ll freak them the hell out and they’ll run away.

Don’t even hold a conversation with them past, “Get out of my front yard now, you are trespassing”. I had two guys come to my door last week and just told them one word, NO" and shut the door. See guys, they call us openly, “The Great Whore of the Earth”. They openly make great fun of us in their Churches and actively proselyte against us for political gain with Protestants, …who they then try to convert as well".
They are the MLM of religion.
Side note: their members are leaving so fast that they are at the moment having trouble functioning as an institution. Why, they have weird beliefs, God and Satan are brothers, god is a man that lives on a Planet near a place called Kolob… and it goes on.
eh, just tell them to get the hell outta your front yard.
Don in Las Vegas