Sahih al-Bukhari 2171

The Prophet (ﷺ) said, "The selling of wheat for wheat is Riba (usury) except if it is handed from hand to hand and equal in amount. Similarly the selling of barley for barley, is Riba except if it is from hand to hand and equal in amount, and dates for dates is usury except if it is from hand to hand and equal in amount. (See Riba-Fadl in the glossary)

Aisha, (mother of the faithful believers) wanted to buy a slave girl and manumit her, but her masters said that they would sell her only on the condition that her Wala' would be for them. `Aisha told Allah's Messenger (ﷺ) of that. He said, "What they stipulate should not hinder you from buying her, as the Wala' is for the manumitted

The Prophet (ﷺ) forbade Muzabana; and Muzabana is the selling of fresh fruit (without measuring it) for something by measure on the basis that if that thing turns to be more than the fruit, the increase would be for the seller of the fruit, and if it turns to be less, that would be of his lot. Narrated Ibn `Umar from Zaid bin Thabit that the Prophet (ﷺ) allowed the selling of the fruits on the trees after estimation (when they are ripe)