I host a few client marketing & transactional mails.

Mostly sending stuff from marketing automation/newsletter software.

Not an issue. Will be migrating the first few domains of off paid google workspace E-Mail to a self hosted solution. I actually don’t expect too much trouble.

But that’s currently still a hypothesis. I have seen a few people do that successfully. So I know it’s possible. Still. Not having hosted a mail infrastructure in 20 odd years…