Activation lock check

This is easy:

When you initially power-on the device … it should prompt for a language and show “Hello” … and then launch the setup routine.

If it does ANYTHING else, don’t buy it.

See section titled: “Check for Activation Lock before you buy a device from someone else” in this article:

Activation Lock for iPhone, iPad, and iPod touch - Apple Support

This cautionary article authored by one of the senior ASC Contributors may be provide some useful information - that may cause you to at least pause to carefully reconsider private purchase of a previously used iPad:

The All Too Common SAD Reality of Buying … - Apple Community

Otherwise, here is what Apple suggests when purchasing a previously owned device:

Check for Activation Lock before you buy a device from someone else

Before you buy an iPhone, iPad, or iPod touch, from someone other than Apple or an authorized Apple reseller, make sure that the device is erased and no longer linked to the previous owner’s account. Follow these steps to check if the device is ready to use: 

1. Turn on and unlock the device. 
2. If the passcode lock screen or the Home screen appears, the device hasn't been erased. Ask the seller to completely erase the device by going to Settings > General > Reset > Erase All Content and Settings. Don't take ownership of any used iPhone, iPad, or iPod touch until it's been erased.
3. Begin the device setup process.
4. If you're asked for the previous owner’s Apple ID and password, the device is still linked to their account. Hand the device back to the seller and ask them to enter their password. If the previous owner isn't present, contact them as soon as possible and ask them to use a browser to remove the device from their account. Don't take ownership of any used iPhone, iPad, or iPod touch until it has been removed from the previous owner’s account.

You will know that a device is ready for you to use when you're asked to "Set up your iPhone," “Set up your iPad," or “Set up your iPod” the first time you turn it on.

You should note that the only way to verify that a device is not Activation Locked is to physically check the device in-person. If purchasing privately, beware of common “bait and switch” tactics - where you may be shown an unlocked device - which is covertly switched for another before hand-over.

First go into settings:-

general:-

about:-

find serial number and copy paste on coverage.apple.com, and check warranty as you want to buy old device.

secondly,

check for sim lock if cellular varient.(preferred not to buy if sim locked).

third,

start your device and if your device has successfully started and activated,

it is not on activation lock.

Activation Lock is the process, where it allows us to protect from using from other users.