Here are my trading conditions :
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I have been swapping coins on Internet since 1997 

and for several years without
any problem but in year 2003 I was victim of two
bad traders and then several letters with coins that I sent or that I
was waiting for never arrived. 

So now, I try to be more carefull in my trades. 

First, I am member of  

"Be Safe With Good Traders" group 

and then for other exchanges, I apply these conditions :
1) for any exchange with a new trader, I ask him for lists of good
traders where his name is or  I ask him to send first
2) I ask him if he accepts to make an exchange with a small amount
of coins
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Thanks to give answers to these questions