You can read more about the sites here.
We run and host all our sites our selves. We have VPSs (Virtual Private Servers) on Digital Ocean, managed by ServerPilot and CMSCommander. We use Wordfence and WPBruiser, to safe guard our installs from hackers etc. We also use Jeff Starr's 6G firewall in our .htaccess file. Read more about the technique behind our servers.