Unenroll Managed Chromebook

I need assistance to unenroll a second-hand Chromebook that is currently enrolled in a managed domain. Once unenrolled, I plan to re-enroll it for personal use.

Requirements:
- Expertise in handling Chrome OS devices.
- Experience with unenrolling Chromebooks from managed domains.
- Knowledge of re-enrollment processes for personal use.

Ideal Skills:
- Familiarity with Google Admin Console.
- Technical proficiency in Chromebooks and Chrome OS.
- Ability to provide step-by-step guidance or perform the task remotely.

Please provide your approach and estimated timeline.