Look into benefits from professional organizations and affinity groups

If you belong to professional or alumni organizations, tap the car deals that many of them offer. Also look into the benefits available from business traveler organizations.

I recommend: The American Small Business Travelers Alliance (ASBTA) offers car rental discounts among its member benefits. For a small annual membership fee you can take advantage of discounts from the American Automobile Association (AAA). Age has its privileges too. If you're 50 or better, become a member and take advantage of car rental discounts available from AARP.

Evaluate your rental car needs

Think outside the box: chances are you really don't need to rent a car every time you travel. Unless you require the vehicle to visit customers, make sales calls in out-of-the-way places, deliver products, transport service equipment or provide transportation for others, it's likely there's less expensive transportation that will get you where you need to go.

I recommend: Taxi or rental car? Use this guide for several US cities. Look into other ways to get from the airport to your hotel or conference center.

Quickly compare deals

The internet is a great resource for comparing best-costs on car rentals. Look for sites that do the work for you

I recommend: Look into Hotwire and SideStep for quick-and-easy search tools that will get you to the deals fast. BreezeNet also offers one-stop-shopping for discount car rental deals.

Evaluate offers from smaller rental car companies

Don't rule out the smaller car companies. Just because they don't have as many locations or major corporate backing doesn't mean they won't make a deal.

I recommend: Independent car rental agencies can be a good source for discounts.

Check out the big guys too

A surprising number of major car rental companies offer programs specifically for small businesses.

I recommend: Check out Budget Rental Car's Budget Business Program (voted best car rental value for small and midsize businesses by Entrepreneur Magazine), the Hertz Business Account Program, the Avis Corporate Awards Program, and Advantage Rent a Car's Easy Corporate.