Quick tip for Time Machine backups: Mac OS X Server (“Server.app” these days) can setup a quota for Time Machine backups that is specific per-machine (rather than per-user). This trick works on any share, actually, since it’s a root-owned property list in the share directory. You’ll want Mavericks or later as a client for this to work, but to set it up cd into the root of the Time Machine share and create the plist with (for a 500GB example):