When buying a TI-83 Plus (or any other calculator for that matter), it is important to follow these steps to insure your full satisfaction:

1. Is there a name scratched into the back?

2. Does it come with the link cable?

3. Does it come with the manual?

4. Does it come with the backup battery?

5. Are there any dead pixels?

6. Are any keys jammed or disfunctional?

If the seller does not specifically mention any of these, please make sure to ask the seller. Also, make sure it really is a TI-83 Plus, and not just a TI-83.

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