I can only imagine the horror of running a hosting company. If you want to do it properly, there is no end to complexity. Not to mention the money part. I've always dreamed about running my own niche hosting business, running on dead-stripped Slackware custom boxes for actual serving/hosting and OpenBSD for routers/firewalls/spamd daemons (actually I would not deal with email at all as it is a separate business in it…
Running a hosting company was actually a pretty profitable business back in the 90s. (It probably still can be if you have a really solid niche). I should write some blog posts on our experience (there were many positives).
* email * good customer service for a price