For those who do use taxis, they usually use the same one or two drivers and develop a rapport with them over a period of time.
Pricing depends on the mood of the driver, the mood of the passenger and the distance to be covered.
Bargaining is expected. Once the price is agreed upon, however, the passenger calls the shots, so if you want to drop by to give someone a message or pick up a friend who is walking along, the price remains the same. Naomba nipeleke kiwanja cha ndege. Lower the price please. Punguza bei tafadhali.