Sole agents usually represent one principal in their country and agree that thay will not sell competing through the agency. Sometimes car manufacturers insist their agents only to sell their products, but then the agent will handle the whole range of cars and accessories. The manufacturer may inspect the agency to make sure it has facilities to offer all the service a car buyer would expect from a garage.
A sole agent in return might insist on a contract which states that the principal will not supply any other agency in the agent’s territory. However, this will depend on the economic and practical problems in selling the products. In the case ofcar seles, it is to the agent’s advantage that there are other agencies selling the same make; so that consumers do not have to travel long distances to get their vehicles serviced and maintained.
(Taken from Basic Commercial English – A. ashley).