Have you tried Zipcar? Here's a cheap way to have Wheels When You Need Them

One of the biggest impediments for carsharing to enter a new city is the cost and availability of parking. This is especially the case in cities such as San Francisco, New York and Boston where parking is a premium. It is also an issue in Midtown and downtown Atlanta.
Through a unique partnership between Lanier Parking Solutions and Zipcar, we were able to address this concern. Lanier provides free parking for Zipcars, enabling carsharing to come to our city years before the market would have allowed it.

Special deal on Lanier Zipcar

You can try Lanier Zipcar at a discount. If you apply using this link, Zipcar will waive the $25 application fee and cut your annual fee in half to just $25. You'll also get discounted hourly and daily rates.
Check it out, and let me know how it goes.
If you're not familiar with Zipcar, read this story that the AJC did in September.