When you spend weeks or months shopping from shops or markets around your place, you will have known the perfect seller for you. You will always have a favorite shop that sometimes you would postpone buying an item when you find the shop is closed. There is a shopkeeper at my estate who is now friends with my parents. We can take goods from him on credit and pay later because he trusts us and we trust him. We could go to other shops once in a while but his shop was our favorite. Do you have a favorite market or shop and what do you benefit from depending on one supplier?