有關yahoo auction, 這樣的信件是否騙人?

在yahoo auction 的發問區，很有趣地，我看了這兩個發問。其中，case 1 buyer 的出價$2400 比seller 的還高，這是可疑點之一。另外，case 1&2 同是來自United Kingdom、寫信的格式相近，而且兩者皆要求提供有關銀行的資料。那麼，兩人會否是騙徒抑或黑客? 如果是騙人的，他們又會是如何令人受騙?
有興趣或有相關經驗，皆可解答。
謝謝~
case 1(所有name 皆以x代替)
Hi Seller,My Name is xxx,i am from United Kingdom. I will like to make an urgent purchase of this yahoo auction item as gift AND I WILL BE WILLING TO OFFER HKD$ 2,400. As for the payment i will be paying via BANK TO BANK WIRE TRANSFER and your money will be transfer directly to your bank account via BANK OF AMERICA (BOA) AND SHIPMENT VIA speed post Express. Reply me or add me to xxxx.

Hope to read from you soon.
case 2(所有name 皆以x代替)
Dear seller,
XXX Is My Name From United Kingdom,I'm
interested in Buying your Item . What is the present condition and how much do you want to sell
it last?I'm buying it urgently for son programmed in college.kindly let me know how the total cost of it and I am ready to pay for the item immediately do kindly get to me
back with the total cost of the item And Even Let me know if you still Have anyother Item for sale maybe i can still buy it for my son ..I will be making payment via bank to
bank transfer. Do provide your info for immediate payment: Account name,Account Number, Bank Name,
Bank address, bank code: alongside your response..while you also provide
me the cost of the shipment through(DHL 2-3Days) and i want you to reply me
back in English and don't forget to send me your real e-mail and you can also reply me back to XXXAwaiting to hear from you...