Rental Car Magic is a rental car rate search service. They do not rent cars and have no affiliations with any rental car agency.
They use a customized search process to maximize the use of special promotions and discounts in combination with standard rates to produce savings. These special rates are often hard to find and restricted to specific groups,certain days, dates, locations or vehicle types. However, when properly applied, these discounts can result in very significant rate reductions.
You tell them where, when and what type of rental car you're looking for. They'll search special discounts and promotion to find you the lowest rate which matches your needs. You make the rental reservation with the details that they provide to you.
The site, which charges $14.95 to $49.95, sends back a quote in a day or two.
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Hat Tip to NYTIMES Practical Traveler.