How to Powerwash Chromebook
Here is a link to a video on how to powerwash your Chromebook and also steps to do it...
Step by Step Directions:
Turn off the Chromebook.
A yellow exclamation point (!) or "Please insert a recovery USB stick" is displayed.
Press Ctrl+D to begin Developer mode, then press Enter.
Press Space, then press Enter.
The Chromebook deletes its local data, returning to its initial state. This can take approximately 40 minutes.
Note: If Forced re-enrollment is enabled for the device, you'll see a note that Developer mode is blocked. This shortens the wipe process, and still allows for re-enrollment when the device automatically restarts in Verified mode.
When the transition completes, press the space bar, then press Enter to return to Verified mode.