Sahih al-Bukhari Book 34, Hadith 90
Rarely did the Prophet (ﷺ) fail to visit Abu Bakr's house everyday, either in the morning or in the evening.
When the permission for migration to Medina was granted, all of a sudden the Prophet (ﷺ) came to us at
noon and Abu Bakr was informed, who said, "Certainly the Prophet (ﷺ) has come for some urgent
matter." The Prophet (ﷺ) said to Abu Bark, when the latter entered "Let nobody stay in your home." Abu
Bakr said, "O Allah's Messenger (ﷺ)! There are only my two daughters (namely `Aisha and Asma') present."
The Prophet (ﷺ) said, "I feel (am informed) that I have been granted the permission for migration." Abu
Bakr said, "I will accompany you, O Allah's Messenger (ﷺ)!" The Prophet (ﷺ) said, "You will accompany me."
Abu Bakr then said "O Allah's Messenger (ﷺ)! I have two she-camels I have prepared specially for migration,
so I offer you one of them. The Prophet (ﷺ) said, "I have accepted it on the condition that I will pay its
price."
I saw the people buy foodstuff randomly (i.e. blindly without measuring it) in the lifetime of Allah's Apostle and they were punished (by beating), if they tried to sell it before carrying it to their own houses.
Allah's Messenger (ﷺ) said, "Do not urge somebody to return what he has already bought (i.e. in optional sale) from another seller so as to sell him your own goods."