I'm running a mix of small VPS and dedicated servers (most of them below 20€/month), including for receiving emails. Once you've spent some time tinkering with them, taming the OS, and stuff, it's much more flexible than any SaaS. And probably way cheaper, too.

I use 3rd party services for sending mails, though. The amount of boring work to get out of my recipients' spam folder is just too high without that.