If you’re still unsure, I’d say try running your own email server (it’s free afterall)
When to Use a Third-Party Mailing Service and When to Host Your Own Email Server
Feeling OK

It’s free if and only if your time is worth nothing, and you’re willing to accept the risk of things breaking at inconvenient times. I’ve enjoyed running a mail server in the past, but the rigmarole of running and locking down SMTP and IMAP servers, keeping up with disappearing anti-spam blacklists, handling anti-spam authentication DNS mechanisms, and being on call in case of emergency— it’s a lot to ask of someone.

When in doubt, it’s best to avoid complexity.