Jabir bin Abdullah (may Allah be pleased with them both) says that he sold a camel to the Prophet (peace and blessings of Allah be upon him) on the way and made it a condition that he would ride it to his family. 1
Imam Tirmidhi says: 1- This hadith is Hasan Sahih. 2- This is also narrated from Jabir through other chains. 3- Some of the Companions and others among the people of knowledge act upon this. They consider a condition in a sale to be permissible when there is only one condition. This is also the view of Ahmad and Ishaq bin Rahwayh. 4- And some of the people of knowledge say that a condition in a sale is not permissible, and when there is a condition in it, the sale is not complete.
Hadith Referenceسنن ترمذي / كتاب البيوع عن رسول الله صلى الله عليه وسلم / 1253