Abu Labid (may Allah have mercy on him) narrated from Sayyiduna Urwah al-Bariqi (may Allah be pleased with him) that the Prophet (peace and blessings be upon him) came to a herd of animals (brought for sale). He (peace and blessings be upon him) gave him a dinar and said: "Buy a sheep for us." He went and bought two sheep for one dinar. Then a man met him, so he sold him one sheep for a dinar. Then he came to the Prophet (peace and blessings be upon him) with a dinar and a sheep. The Prophet (peace and blessings be upon him) said to him: "May Allah bless you in your transaction." Urwah (may Allah be pleased with him) said: (Through the blessing of that supplication) I would stand in al-Kunasah (market) and would not return to my family until I had made a profit of forty thousand.
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 14493