Want to add a rental car or hotel to your flight reservation? Here’s why you shouldn’t bundle your travel bookings.

This is reprinted by permission from . 

Bundling is a practice popularized by third-party, online travel agencies, like Expedia EXPE, Priceline and Kayak, that encourages booking flights, hotels and rental cars in the same reservation. The option to bundle is also often offered through travel providers (such as when a popup surfaces on an airline’s website asking you to book a rental car, too).

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