Abu Hurairah reported,

The Messenger of Allah ﷺ said, "Do not go out to meet the caravans before they reach the market, and let none of you outbid another in a sale already being negotiated. Do not inflate prices artificially, and let no townsman sell on behalf of a desert dweller. Do not tie up the udders of sheep to make them appear to give more milk. Whoever buys such an animal has the choice, after milking it, between two options. If he is pleased with it, he may keep it, and if he is displeased, he may return it along with a measure of dates."

Bukhari 2150

Sahih

حدثنا عبد الله بن يوسف أخبرنا مالك عن أبي الزناد عن الأعرج

عن أبي هريرة رضي الله عنه

أن رسول الله ﷺ قال لا تلقوا الركبان ولا يبع بعضكم على بيع بعض ولا تناجشوا ولا يبع حاضر لباد ولا تصروا الغنم ومن ابتاعها فهو بخير النظرين بعد أن يحتلبها إن رضيها أمسكها وإن سخطها ردها وصاعا من تمر

البخاري 2150صحيح
Contents
Reference
Commentary
Ayat
Collection
Sahih Bukhari
Book
Sales
Chapter
Prohibition for the seller against tying up the udders of camels, cows, and sheep, and every animal with tied udders
Numbering
Darussalam 2150
Bukhari 2150