“No tow-dweller should sell for desert-dweller, no man should outbid his brother; and no woman should ask for her sister (in faith) to be divorced so as to turn over what is in her bowl (deprive her of her share of maintenance)”
the Messenger of Allah sold a drinking bowl and a blanket (for a horse of camel) to the highest bidder ‘
the Messenger of Allah forbade Mulamash and Munabadha.
“No one of you should urge someone to cancel a sale he has already agreed upon with his brother so as to sell him his own goods.”
“Do not urge someone to cancel a sale he has already agreed upon so as to sell him your own goods, unless he bys or changes his mind.”
the Prophet forbade artificially inflating prices.
“The Messenger of Allah said: ‘Do and whoever meets any of them and buys from him the vendor has the choice of annulling the transaction when he comes to the marketplace.”‘
The Messenger of Allah said: “No town-dweller should sell for a desert-dweller, do not artificially inflate prices, no man should urge a seller to cancel a sale already agreed upon with another buy so as to by the goods himself, no one should make a proposal over the proposal of his brother and no woman […]
“The Messenger of Allah (ﷺ) forbade meeting traders on the way, until one enters the market with them?” Abu Usamah acknowledged it and said: Yes.
“What does a town-dweller (selling) for a desert-dweller mean?” he said: “He should not act as a broker for him,”