If you're flexible and only need a car occasionally, you can avoid the hefty costs of buying and maintaining a vehicle with a process known as car sharing. Zipcar and Flexcar are both popular car-sharing companies that allow you to reserve a vehicle and borrow it. The system is perfect for short-term sharing, because fees can be on an hourly or daily basis.
The cars are usually stationed in reserved parking spots in convenient locations on streets around a city. For Zipcar, all you have to do after reserving the car is unlock it with your personal Zipcar card. When you're done with the car, you return it to the spot where you picked it up. Zipcar includes gas and insurance in the annual and hourly or daily rates.