Never pay in advance to a seller that you do not know.
Even if the seller discloses his/her personal information or bank account number, this does not protect you from being cheated.
Always request for the original receipt of purchase from the seller, to verify that he/her is the rightful owner of the item; and to verify that the item is authentic.
Avoid sending goods or payment; instead, meet in person and do COD (Cash on Delivery).
For Rent 
