Ibn 'Umar (Allah be pleased with them) reported Messenger of Allah ﷺ as having said this: One amongst you should not enter into a transaction when another is bargaining.

حَدَّثَنَا يَحْيَى بْنُ يَحْيَى، قَالَ قَرَأْتُ عَلَى مَالِكٍ عَنْ نَافِعٍ، عَنِ ابْنِ عُمَرَ، أَنَّ رَسُولَ اللَّهِ ﷺ قَالَ
" لاَ يَبِعْ بَعْضُكُمْ عَلَى بَيْعِ بَعْضٍ " .