Abu Safwan Suwaid bin Qais (May Allah be pleased with him) reported:
Makhramah Al-'Abdi and I procured some drapery from Hajar and brought them to Makkah. The Prophet (ﷺ) came and bargained with us for some trousers and we sold them to him. We had a person who weighed the cloth in order to fix the price. The Prophet (ﷺ) said to him, "Weigh and add a little to it."[Abu Dawud and At- Tirmidhi].
App reference: Book 12, Hadith 91
Arabic/English book reference: Book 12, Hadith 1375