How do you know if a buyer email is a scam?

The following is an example of a buyer scam email:

----- Original Message -----
From: XXXXXX
To: XXXXX Sent: Friday, December 10, 2004 3:24 AM
Subject:
Car/Thanks for the reply willing to pay

Goodday Sir,
          
   How are you doing today, i have seen the car and i think is great. I have accepted to pay the stipulated price immediately with a bankers draft , just that the draft, is going to be in an amount larger than the cost of the car.
 
Reason being that it is a refund payment to me and the Creditor issuing the check has the policy not to issue more than one check to a refund payment, which means that the check is going to carry the whole amount em-block for the sales and shipping of the car from USA to UK.
 
The check that will be sent to is $6,000.00 and you would have to deduct the cost of your car $2,900.00 from it immediately you cash it and send the balance $3,100 via wire transfer (MoneyGram) to offset the shipping charges. So, I am entrusting you to handle this funds with honesty, care and utmost confidentiality.
 
You are required to send Name, which should be on the check, the address where the check is going to be sent and your contact telephone numbers for fast communication. On receipt of this information, the check will be sent to you. After you send the balance, the shipper will be paid and they will come and pick up the car immediately.
 
Ask question where you are not cleared. I would be there to explain further. Please send more pictures of the car. You can reach me via phone any time on 002348-0358-38370.
 
Looking forward to rounding up this transaction as soon as possible.
 
Thanks and have a wonderful day.
 
Smith.