Ubaidullah bin 'Umar bin Hafs عبيد الله بن عمر بن حفص بن عاصم · The Book of Financial Transactions

"The Messenger of Allah said: 'One of the portents of the Hour will be that wealth becomes widespread and abundant, and trade will become widespread, but knowledge will disappear. A man will try to sell something and will say: "No, not until I consult the merchant of banu so and so: and People will look throughout a vast area for a scribe and will not find one." (Sahih )

"whoever buys a Musarraha, if he is please with it when he milks it, he may keep it, and if he is not please with it, he may return it, along with a Sa of daters"' (Sahih )

"It was forbidden to us for a town-dweller to sell for a desert-dweller." (Sahih )

"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 '

"Whoever sells fruit then his crop fails, he should not take (anything) from his brother." (And he said something along the lines of) "Why would anyone of you consume the wealth of his Muslim brother?"

"Whoever buys food let him not sell it until he has taken possession of it."

the Prophet bought a horse from a Bedouin and asked him to follow him, so that he could pay him for the horse. The Prophet hastened but the Bedouin was slow. Men started to talk to the Bedouin and make offers for the horse, and they did not realize that the Prophet had bought it, until some of them offered more than the Prophet had bought it for. Then the Bedouin called out to the Prophet and said; "Are you…