Ensure "Find My" is turned off. If a Mac is Activation Locked, it is useless to you.
Explain the chips for your needs? Provide a pricing guide for current used market values? how to safely buy a used macbook
Check System Settings > Privacy & Security > Profiles . if a "Management" profile exists, the laptop belongs to a company and can be remotely locked. Ensure "Find My" is turned off
Before exchanging money, you must verify the device is not legally or digitally locked. Provide a pricing guide for current used market values
Turn brightness to max. Look for "dead pixels" or bright white spots (backlight bleed).
Restart the Mac and hold Option (⌥) . If a padlock icon appears, it has a firmware password. Do not buy it.
Facebook Marketplace or Craigslist offer the lowest prices but have the highest risk. Always meet in a public, well-lit place.