If you purchase somebody else's phone, it may still hold the warranty from the original purchase. It depends on specifics of the situation, such as the type of account involved and the history of the phone. If it malfunctions, it doesn't hurt to call warranty at 1-800-801-1101 to ask. If you do, please let the agent know you purchased the phone directly from somebody else (or through an auction site, or whatever the case is). If you know the phone number it used to have, that's good information, too.
As the previous poster said, I don't believe you can insure the device.
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