سلسلة كتاب المسدرك على الصحيحين الجامع بين صحيح البخاري و مسلم ب12 مجلد
"Mstaml & New" warns against dealing outside the application and strongly advises dealing through private messages only and dealing hand in hand and beware of intermediaries and make sure that the bank account belongs to the same person who owns the commodity.