case description:
we were scammed by one of our clients. we are exporting silk ties from china. this client is a korean, but he is doing business in spain. we exported to his korean agency as per our contract. then his korean company sent the products to spain. it worked well for several small order; we received quick payment after we sent out our products. then this client wanted to place a larger order and requested to prolong the payment time. considering our good cooperation from last order, we accepted his suggestion. then we never received our 7000usd. this client always gave me the excuse that he can not arrange payment because of a problem with his korean partner. it has been half a year now and still i haven't received the payment. 
 
analysis of this case:
1. it is an advanced fraud trick; the fraudster will use the psychology of the supplier to conduct fraud activities. he will place small orders first and transfer payment quickly to convince the supplier he is a good partner. then he will place a large order and set a trap for supplier. based on the good cooperation of previous business, the supplier will fall into the trap easily.
 
2. always follow normal foreign trade processes when doing business with your partner.