question #2 Sahih al-Bukhari 7350, 7351, Book 96, Hadith 78 : How should one conduct transactions to ensure fairness and avoid exploitation in trade?

Allah’s Messenger (ﷺ) sent the brother of the tribe of Bani Adi Al-Ansari as governor of Khaibar. Then the
man returned, bringing Janib (a good kind of date). Allah’s Messenger (ﷺ) asked him, “Are all the dates of
Khaibar like that?” He replied, “No, by Allah, O Allah’s Messenger (ﷺ)! We take one Sa’ of these (good)
dates for two Sas of mixed dates.” Allah’s Messenger (ﷺ) then said, “Do not do so. You should either take
one Sa of this (kind) for one Sa’ of the other; or sell one kind and then buy with its price the other kind
(of dates), and you should do the same in weighing.”