Is the buyer overseas? If you are concerned I would cancel the sale and use the reason "problem with buyer's address" then you will receive a credit for your final value fees.   As the payment is on hold, don't refund, let the cancellation process take its course.  

did the buyer ask to send to an address different to the PayPal address?  If so,  DO NOT post to any address other than the PayPal address if you go ahead with the transaction