Car sharing is a type of business that allows members to borrow cars for personal use for an hourly fee. Members use car sharing as an alternative to owning a car or using public transportation. It can be most useful for grocery shopping, dropping off recycling, or driving to a place that isn't easily accessible by public transportation.

What is Car Sharing?

Car sharing is a type of business that allows members to borrow cars for personal use for an hourly fee. Members use car sharing as an alternative to owning a car or using public transportation. It can be most useful for grocery shopping, dropping off recycling, or driving to a place that isn't easily accessible by public transportation.

Using a car share is similar to renting a car, in that they both involve borrowing a car for a fixed period of time, but car sharing and traditional rental services differ in several fundamental ways. Whereas traditional rental car agencies offer car rentals at a fixed daily rate and are generally intended for travelers, car shares are typically billed by the hour (although daily rates are also offered), and they are mostly meant for local or in-town use. Unlike rental cars, car-share cars are completely self-serve, and as such they are not cleaned between uses, and they aren't re-fueled by a rental agency. Members are expected to keep the cars clean and to fill them up with fuel.

What's the difference between I-GO and Zipcar?

In Chicago, the two biggest car-sharing companies are the locally-owned I-GO, which was created by the Center for Neighborhood Technology, and Zipcar, one of the world's biggest car-sharing companies. Both companies have cars parked across the city, but options become quite limited on the South and West sides -- and also on the North Side, west of the Kennedy Expressway.

In 2009, I-GO and the Chicago Transit Authority launched a joint smart card program that enables users to use a single card to access I-GO vehicles and to ride the CTA.

Both I-GO and Zipcar have more than 200 cars in Chicago, and both companies seem to have similar business models, but the most basic difference is in price and the types of cars offered. While I-GO's fleet of cars seem to be oriented towards fuel efficiency, Zipcar offers a wider range of options, including some luxury models. One other benefit to Zipcar is that it is offered in many other American cities, and a Zipcar membership in one city enables you to use a car anywhere in the country. I-GO only has cars in the Chicago area.

How does it work?

Once you decide when you'd like to reserve a car and for how long, you can log onto the car-share company website to make a reservation. If no car is available at your desired location, the website will offer a list of nearby locations that do have available cars during the alloted time.

When you sign up with either I-GO or Zipcar, you are issued a magnetized plastic card, which serves as a key. After making a reservation, go to the car and hold the plastic key card up to the sensor on the windshield to unlock the doors. The ignition key is found inside the car, along with a gas card, which you should use whenever the gas level dips below one-quarter tank.

How much does it cost?

Zipcar and I-GO both have similar pricing structure: Users sign a contract and pay a fee to use the cars for the length of time specified in the contract. The most common contract is for a year-long membership, which costs $50 annually for both companies.

In addition to the year-long membership, I-GO offers a few shorter options, including the GO Budget six-month membership, has a lower membership fee ($15 for six months), but costs more per hour ($7 to $12 per hour). Membership and rates include the cost of insurance and fuel. Both companies also charge $25 for an application fee.

What if I crash or otherwise damage the car?

For both Zipcar and I-GO, insurance is included in the annual fees and hourly rates, but if the I-GO or Zipcar member is determined to be at fault, they have to pay a deductible of $500. For Zipcar, the insurance covers a combined limit of $300,000 per accident, which includes damage to all cars and people involved. I-GO also offers a limit of $300,000 per accident, as well as a $5,000 limit for medical payments.