In my 20 years of outsource IT career I’ve helped lots of business moguls with their personal home mail servers, since I already support their business IT. This doesn’t mean it’s easy, it means they’ve got money to ask someone to do it.
I’m going to tell you, it’s all nice and easy if you understand servers, backup, networking, dns, and security. If you don’t, you’ll probably get it working, for a while, until it doesn’t.
Why do you pay IT if it’s already working? Why do you pay IT if it’s not working?
My caption to this could have been “A self fulfilling prophecy”.