I was using Mail Chimp but they don’t offer automations on the free tier. I purchased Convert kit, but paying $300+ a year for tutorials I give away for free does not make sense.
Hosting a personal email server works fine on some providers assuming one sets up FCrDNS, DMARC, and finds a clean IP. By personal email server I mean that one sends emails to their friends and family. Some providers are starting to require people to prove they comply with the CAN SPAM act [1]. Once that server starts targeting random or large numbers of people it will be promptly sink-holed off the internet and the VPS account would be at risk of suspension.