You’ll never get away from maintenance for ant service you host, and you need a VPS at a minimum to handle mail unless your ISP allows it (which they probably don’t). There’s going to be front loading needed in order to make sure the IP you’re given isn’t on blocklists, and you’ll need to take appropriate measures with Apple, M$, Google, Yahoo, etc in order to send email to their domains. The good thing is that I’ve you do that, you’ll never need to touch it again.
I personally use iRedMail because of the breadth of documentation, but mailcow and others like that are allegedly nice. I prefer the omnibus solutions because I don’t care to do manual service configuration if it’s not necessary.
Been doing email hosting for my domain for 25 years, 12 years with iRedMail.
What percentage of those are bots?