Nice to See an Article About This
I'm glad to see an article tackling this subject, as I agree it's not that hard to set up an email server, and as long as you have a sufficient broadband connection with reasonable upload as well as download speeds, it's worth doing.
Although it's offline for an annoying reason at the moment (not related to the PC or software), a couple of years ago I set up my own email server based on an Acer Revo 3700 (and a couple of gateways and a mail server were on such PCs as well) using ClearOS 6. It was connected to a Plusnet Fibre connection with a static IP, and once I'd solved installing the SOGo groupware on it, worked like a dream with Thunderbird. I couldn't get the Outlook Connector side of things to work, but that was down to ClearOS 6 being based on a version of RedHat that was too old for some of the components that SOGo's Outlook Connector needed.