I would like to share some of the knowledge I have acquired about some scammers that tried to fool me twice.
Basically these people open several eBay account in UK (or they hack some) so that they figure as regular customers and resident in UK. They sell and buy small and cheap stuff among the different account in order to get perfect feedback. Once their feedback has reached, say, 10 positive they start hunting for the unaware seller.
Usually they target small expensive stuff that is easy to send by courier but that has a great intrinsic value such as electronic equipment, laptops, mobile phones and so on.
They then bid on your auction increasing the price as to win the item, or they send you an email saying if you are willing to end the auction earlier for a price. They seem to be honest and they offer to pay you through Paypal for your peace of mind. They also ask for you email address in order to communicate easily with you.
After either they win the auction or you agree to interrupt it they ask you to send the item in some African country (the preferred by the scammers that targeted me was Nigeria) by express courier. They want to address the item to their partner/lover/distant relative in order to give them a surprise for their anniversary/birthday and so on... HOW SWEET OF THEM! The problem is that they want YOU to pay for their gifts!
Now the scam really kicks in: they send you a bogus email, supposedly from Paypal, that says that the money they owe you are waiting on your account and to unlock them you need to enter the code of the shipment of the item that the espress courier gave you when you shipped the item. The problem is that Paypal does not have any idea of the this transaction and hence there is no money waiting anywhere! In fact this is not standard Paypal procedure, it never asks you for the proof of shipment of the item.
The very first time this happened to me, this person won the auction and asked me to send the mobile in Africa. I sensed something was wrong and I give a false code to see what was going to happen. The eBayer thanked me very much and I received a letter from Paypal saying that the money was for me to collect... only that the money never arrived and I never received a complaint from the winner fo the auction because I never sent the item anywhere!
My advice is to ask for a telephone number of the person, an address, something traceable. Not to send anything to anyone unless you have the money secure in your account.
Be aware of these people, they wake up every morning with a new idea on how to part you from your hard earned money!
Hope this guide helps to reduce this kind of crimes on Ebay.