Seller changing his price for different customers
Q: We chose a cow for qurbaani. The seller is charging other customers R38 per kg. When he sent the bill to us, it was R41.50 per kg. My husband queried it and the seller responded that he has his own system of working out the cost which he does not have to explain, and we can cancel the purchase if it is not suitable to us. Is it permissible for him to conduct business in this way?