Sahih al-Bukhari 2110
Narrated Hakim bin Hizam:
The Prophet (ﷺ) said, "The buyer and the seller have the option of canceling or confirming the bargain 
unless they separate, and if they spoke the truth and made clear the defects of the goods, them they 
would be blessed in their bargain, and if they told lies and hid some facts, their bargain would be 
deprived of Allah's blessings."
حَدَّثَنِي إِسْحَاقُ، أَخْبَرَنَا حَبَّانُ، حَدَّثَنَا شُعْبَةُ، قَالَ قَتَادَةُ أَخْبَرَنِي عَنْ صَالِحٍ أَبِي الْخَلِيلِ، عَنْ عَبْدِ اللَّهِ بْنِ الْحَارِثِ، قَالَ سَمِعْتُ حَكِيمَ بْنَ حِزَامٍ ـ رضى الله عنه ـ عَنِ النَّبِيِّ صلى الله عليه وسلم قَالَ ‏
"‏ الْبَيِّعَانِ بِالْخِيَارِ مَا لَمْ يَتَفَرَّقَا، فَإِنْ صَدَقَا وَبَيَّنَا بُورِكَ لَهُمَا فِي بَيْعِهِمَا، وَإِنْ كَذَبَا وَكَتَمَا مُحِقَتْ بَرَكَةُ بَيْعِهِمَا ‏"‏‏.‏