Abu Al- Qasim said: "Whoever buys a Musarrah, he has the choice (of annulling the deal) for three days. If the wishes ti keep it, he may keep it, and if he wishes to return it, he may return it, along with a Sa of daters, not wheat." (Sahih )
"The Messenger of Allah forbade meeting (the traders on the way) a Muhajhir selling for a Bedouin, keeping the milk in the udder of an animal (so as to increase its price), artificially inflating prices, a man to urge the cancellation of sale already agreed upon and a woman to ask that her sister (in faith) be divorced."
"The Messenger of Allah said: 'A town-dweller should not sell for a direst-dweller. Leave the people alone and let Allah provide for them from one another."" (Sahih )
"Do not go out to meet the riders, and do not urge someone to cancel a sale he has already agreed upon os as to sell him your own goods, do not artificially inflate prices, and let not a town-dweller sell for a desert-dweller." (Sahih )
the Messenger of Allah forbade artificially inflating prices, meeting traders on the way, and for a town-dweller to sell for a desert-dweller." (Sahih )