Bukhari Hadith Volume 3, Book 34, Number 264:
Narrated Ibrahim bin Sad from his father from his grand-father:
Abdur Rahman bin Auf said, "When we came to Medina as emigrants, Allah's Apostle established a bond of brotherhood between me and Sad bin Ar-Rabi'. Sad bin Ar-Rabi' said (to me), 'I am the richest among the Ansar, so I will give you half of my wealth and you may look at my two wives and whichever of the two you may choose I will divorce her, and when she has completed the prescribed period (before marriage) you may marry her.' Abdur-Rahman replied, "I am not in need of all that. Is there any market-place where trade is practiced?' He replied, "The market of Qainuqa."
Abdur-Rahman went to that market the following day and brought some dried butter-milk (yogurt) and butter, and then he continued going there regularly. Few days later, 'AbdurRahman came having traces of yellow (scent) on his body. Allah's Apostle asked him whether he had got married. He replied in the affirmative. The Prophet said, 'Whom have you married?' He replied, 'A woman from the Ansar.' Then the Prophet asked, 'How much did you pay her?' He replied, '(I gave her) a gold piece equal in weigh to a date stone (or a date stone of gold)! The Prophet said, 'Give a Walima (wedding banquet) even if with
one sheep .' "