Abstract: A car hire service is a form of public transportation that enables a group of people to share vehicles based at certain stations by making reservations in advance. The main objective of car hire companies is to provide quality services to its customers by providing prompt services when required. These companies compete one another and have clients locally and internationally. One of the common problems of car hire is that companies can have difficulty optimizing the number of vehicles in operation. This paper reports on investigations of the relationship between the number of cars and the number of reservations per day with either the acceptance ratio or utilization ratio based on the commercially operational dataset of a cars hire company in Kenya. This paper creates an analytical mode to enable this company estimate their daily costs by looking at the distance to be travelled, route type and car type. A simulation model is also constructed to simulate the best booking policy for the company.