classified ad scam

We placed an advertisement in the CC classified section to sell our caravan. It was the manufacturers top of the range and less than 3 years old, priced competitively.The next day we received an e mail offering the full asking price if he could pay by PayPal.This we declined, stating that we were unwilling to pay the seller's fee to PayPal of several hundreds of pounds.He then agreed to pay this on top of the asking price.The next thing he said was that he was presently abroad but would arrange collection of the van but could we pay the courier through the Moneygramme system as he was too far away from one of their offices to do this himself.Their fee he also would pay.He did give us a name and address in England and when we asked where the van was going he said "abroad".This all seemed too good to be true, so we declined his offer,had to P/Ex van at a much reduced price of course ! This has to be a scam but cannot see how, has any one else had a similiar experience?