I hate to say this but even for dedicated self hosters it’s almost never worth it to self host email, either at home or hosted on some rented server or via some IP tunnels.
The reason being is that even after you set up DKIM and SPF and DMARC perfectly you will still need to fight to keep your IPs off of spam lists.
It’s somewhat doable but at the cost of:
- Your email being unreliable and not making it to the destination inbox, AND you not knowing if it went to spam or the inbox.
- You will need to dedicate a few hours a week to appeal and scan spam lists for your IP.
If anyone in the /16 that your IP lives in sends spam you get re added to the list.
Self hosting email is almost never worth it. I self host everything except for email and maps. Those two just are not worth it.