The Messenger of Allah (ﷺ) as saying: A townsman must not sell for a man from the desert ; and leave people alone, Allah will give them provision from one another.
Sunan Abi Dawud Book 24, Hadith 27
← Previous Hadith That a bedouin told him that he brought a milch she-camel in the time of the Messenger of Allah (ﷺ). He alighted with Talhah ibn Ubaydullah (and wanted to sell his milch animal to him). He said: The Prophet (ﷺ) forbade a townsman to sell for a man from the desert. But go to the market and see who buys from you. consult me thereafter, and then I shall ask you (to sell) or forbid you.

Sunan Abi Dawud Book 24, Hadith 26 Next Hadith → The Messenger of Allah (ﷺ) as saying: Do not go out to meet riders to conduct business with them ; none of you must buy in opposition to one another; and do not tie up the udders of camels and sheep, for he who buys them after that has been done has two courses open to him after milking them: he may keep them if he is pleased with them, or he may return them along with a sa' of dates is he is displeased with them.

Sunan Abi Dawud Book 24, Hadith 28