Q: Buying a used macbook

   Visual Inspection

   Hands on experience

   Apple Diagnostics Test:   http://support.apple.com/en-us/HT202731

   EtreCheck:  https://discussions.apple.com/docs/DOC-6173

   Giving away / Selling your Mac / Resetting  the computer to  factory condition

  http://support.apple.com/en-us/HT201065

  http://www.thesafemac.com/how-to-prepare-your-mac-for-sale/

  If there is any existing problem, you can take this  Mac to an Apple store to have it checked out.

  Fee may apply.