I had the experience of selling an item only to find that the person reveresed the payment after two days.  Luckily I did not ship the Elmos.  Make sure the buyer has a confirmed address, even if it is confirmed it does not stop them from reversing the payment.  Second, do not ship right away to give the funds enough time to clear, check with paypal to find out when the final date is that the transaction can be reveresed.  In my case it was reversed after two days of the end of the sale.  Third and most importantly CHECK THE FEEDBACK.  Zero feedback can lead to trouble without proper inquiry.

Good luck, be on guard, have a safe and blessed holiday season.