Q. I made a reservation through Travelocity and had to change the travel dates. Travelocity charged me a fee, on top of what the airline charged. Plus, of course, I paid a $6 booking fee. Do all online travel agencies charge these fees? Why should I even use them?

A. Most online agencies do charge booking fees, although Priceline currently does not. However, they are the most restrictive when it comes to making changes to your ticket, whereas most other sites do allow changes/cancelations for a price. For ex., Travelocity customer care charges $30 for such changes, but you may be able to skirt that fee by calling the airline directly.

As for the advantage of using sites like Travelocity, Orbitz, and Cheapair, if your dates are flexible they have excellent flexible date search options, and they compare fares on many different airlines at a glance. And sometimes they have lower fares than the airline sites (Sometimes not). Most airline sites have limited flexible date search functionality if they have it at all.