tl;dr: If you're trying to follow Kenn White's My $169 development Chromebook and the Google account you're using on the Chromebook is associated with a Google Apps For Your Domain domain, there will be ... issues. You'll quickly discover that at the "Turn on the Play Store" step, doing that for GAFYD domains is controlled by your domain administrator. I happen to be my domain administrator, and I quickly fell into a morass of device management and device enrollment and licenses and and and.
An update once I figure it out.