Sahih Bukhari 2159

Narrated Abu Huraira: Allah's Apostle said, A buyer should not urge a seller to restore a purchase so as to buy it himself, and do not practice Najsh; and a town dweller should not sell goods of a desert dweller. ..

Narrated Anas bin Malik: We were forbidden that a town dweller should sell goods of a desert dweller. ..

Narrated Abu Huraira: The Prophet forbade the meeting (of caravans) on the way and the selling of goods by an inhabitant of the town on behalf of a desert dweller. ..

Narrated Tawus: I asked Ibn `Abbas, What is the meaning of, 'No town dweller should sell (or buy) for a desert dweller'? Ibn `Abbas said, It means he should not become his broker. ..

Narrated `Abdullah: Whoever buys an animal which has been kept unmilked for a long time, could return it, but has to pay a Sa of dates along with it. And the Prophet forbade meeting the owners of goods on the way away from the market. ..

Narrated `Abdullah bin `Umar: Allah's Apostle said, You should not try to cancel the purchases of one another (to get a benefit thereof), and do not go ahead to meet the caravan (for buying the goods) (but wait) till it reaches the market. ..