Shaqayq bin Salmah al-Asadi شقيق بن سلمة الأسدي أبو وائل الكوفي · The Chapters on Business Transactions

"We were sitting in a gathering, and the Prophet (ﷺ) came with traces of water on his head. One of us said to him: 'We see that you are of good cheer today.' He said: 'Yes, praise is to Allah.' Then he spoke to the people about being rich. He said: 'There is nothing wrong with being rich for one who has piety, but good health for one who has piety is better than riches, and being of good cheer…

"The Messenger of Allah (ﷺ) sent us, thirty horsemen, on a military campaign. We camped near some people and asked them for hospitality but they refused. Then their leader was stung by a scorpion and they said: 'Is there anyone among you who can recite Ruqyah for a scorpion sting?' I said: 'Yes, I can, but I will not recite Ruqyah for him until you give us some sheep.' They said: 'We will give you thirty sheep.' So we accepted…

"A man is not to undersell his brother, nor is he to fry to outhaggle his brother."

the Prophet (ﷺ) forbade the Najsh.