There is no set number of cars that you should test drive before making a purchase decision. However, it is a good idea to test drive several different cars that fit your needs and budget. This will give you a better idea of what features and options are available. You should also compare the prices and features of the different cars that you test drive. Finally, make sure to take your time and not rush into a decision. It is better to take a little longer to find the right car than to make a hasty decision that you might regret later.