What to look out for when viewing used laptops?
Are the display hinges okay or stiff?
Are there any breaks in the housing (mostly also in the hinge area)
Are there any screws missing on the underside (= Has anyone ever taken it apart = be careful!)
Are all keys on the keyboard fixed / can all keys be typed
Is the fan noticeably loud / always on?
The display has any pixel errors
Battery, whether buttons, touchpad work, all ports work… These are a few weak points.