Many years ago I sold an item for $40 and the buyer paid using paypal.  They picked the item up and left and promptly cancelled their payment.  Hey presto they got the item for free as when I asked ebay to help with the situation the buyer claimed he paid cash.  And that was that!  I guess things have changed since then.  I didn't sign up to be verified for Managed Payments, I've never heard of that.  If somehow I have their payment I wish I knew where it was so I can give it back to them.