Sahih al-Bukhari, Volume 3, Book 34, Hadith 328 (USC-MSA) ⓘ

Narrated Ibn 'Umar (ra) : We were accompanying the Prophet on a journey and I was riding an unmanageable camel belonging to 'Umar (ra), and I could not bring it under my control. So, it used to go ahead of the party and 'Umar would check it and force it to retreat, and again it went ahead and again 'Umar forced it to retreat. The Prophet asked 'Umar to sell that camel to him. 'Umar replied, "It is for you O Allah's Messenger !" Allah's Messenger told 'Umar to sell that camel to him (not to give it as gift). So, 'Umar sold it to Allah's Messenger. Then the Prophet said to 'Abdullah bin 'Umar "This camel is for you O 'Abdullah (as a present) and you could do with it whatever you like."

وَقَالَ الْحُمَيْدِيُّ حَدَّثَنَا سُفْيَانُ، حَدَّثَنَا عَمْرٌو، عَنِ ابْنِ عُمَرَ ـ رضى الله عنهما ـ قَالَ كُنَّا مَعَ النَّبِيِّ صلى الله عليه وسلم فِي سَفَرٍ فَكُنْتُ عَلَى بَكْرٍ صَعْبٍ لِعُمَرَ، فَكَانَ يَغْلِبُنِي فَيَتَقَدَّمُ أَمَامَ الْقَوْمِ، فَيَزْجُرُهُ عُمَرُ وَيَرُدُّهُ، ثُمَّ يَتَقَدَّمُ فَيَزْجُرُهُ عُمَرُ وَيَرُدُّهُ فَقَالَ النَّبِيُّ صلى الله عليه وسلم لِعُمَرَ ‏"‏ بِعْنِيهِ ‏"‏‏.‏ قَالَ هُوَ لَكَ يَا رَسُولَ اللَّهِ‏.‏ قَالَ ‏"‏ بِعْنِيهِ ‏"‏‏.‏ فَبَاعَهُ مِنْ رَسُولِ اللَّهِ صلى الله عليه وسلم فَقَالَ النَّبِيُّ صلى الله عليه وسلم ‏"‏ هُوَ لَكَ يَا عَبْدَ اللَّهِ بْنَ عُمَرَ تَصْنَعُ بِهِ مَا شِئْتَ ‏"‏‏.‏

Narrated 'Abdullah bin 'Umar (ra): I bartered my property in Khaibar to 'Uthman (chief of the faithful believers) for his property in Al-Wadi. When we finished the deal, I left immediately and got out of his house lest he should cancel the deal, for the tradition was that they buyer and the seller had the option of canceling the bargain unless they separated. When out deal was completed, I came to know that I have been unfair to 'Uthman, for by selling him my land I caused him to be in a land of Thamud, at a distance of three days journey from Al-Madina, while he made me neared to Al-Madina, at a distance of three days journey from my former land.

قَالَ أَبُو عَبْدِ اللَّهِ وَقَالَ اللَّيْثُ حَدَّثَنِي عَبْدُ الرَّحْمَنِ بْنُ خَالِدٍ، عَنِ ابْنِ شِهَابٍ، عَنْ سَالِمِ بْنِ عَبْدِ اللَّهِ، عَنْ عَبْدِ اللَّهِ بْنِ عُمَرَ ـ رضى الله عنهما ـ قَالَ بِعْتُ مِنْ أَمِيرِ الْمُؤْمِنِينَ عُثْمَانَ مَالاً بِالْوَادِي بِمَالٍ لَهُ بِخَيْبَرَ، فَلَمَّا تَبَايَعْنَا رَجَعْتُ عَلَى عَقِبِي حَتَّى خَرَجْتُ مِنْ بَيْتِهِ، خَشْيَةَ أَنْ يُرَادَّنِي الْبَيْعَ، وَكَانَتِ السُّنَّةُ أَنَّ الْمُتَبَايِعَيْنِ بِالْخِيَارِ حَتَّى يَتَفَرَّقَا، قَالَ عَبْدُ اللَّهِ فَلَمَّا وَجَبَ بَيْعِي وَبَيْعُهُ رَأَيْتُ أَنِّي قَدْ غَبَنْتُهُ بِأَنِّي سُقْتُهُ إِلَى أَرْضِ ثَمُودٍ بِثَلاَثِ لَيَالٍ وَسَاقَنِي إِلَى الْمَدِينَةِ بِثَلاَثِ لَيَالٍ‏.‏

Narrated `Abdullah bin `Umar: A person came to the Prophet and told him that he was always betrayed in purchasing. The Prophet told him to say at the time of buying, "No cheating."

حَدَّثَنَا عَبْدُ اللَّهِ بْنُ يُوسُفَ، أَخْبَرَنَا مَالِكٌ، عَنْ عَبْدِ اللَّهِ بْنِ دِينَارٍ، عَنْ عَبْدِ اللَّهِ بْنِ عُمَرَ ـ رضى الله عنهما ـ أَنَّ رَجُلاً، ذَكَرَ لِلنَّبِيِّ صلى الله عليه وسلم أَنَّهُ يُخْدَعُ فِي الْبُيُوعِ، فَقَالَ ‏ "‏ إِذَا بَايَعْتَ فَقُلْ لاَ خِلاَبَةَ ‏" ‏‏.‏