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Anyway, here are some prices what I have found for your trip (dates: 08/20 - 08/27, economy class):
USAirways flights, each with one stop (in Miami) from $509, provided by Travelocity;
the same USAirways flights from $498, directly from USAirways;
American Airways flights from $468, provided by Orbitz;
USAirways flights, each with one stop (in Charlotte) from $509, provided by Expedia;
one-stop USAirways flights from $522.02, provided by CheapFlightSales;
You can search these providers directly or starting from metafares' main page (www.metafares.com). Also deserves a try to look for oneway airfares (ORD->SJO, SJO->PHL). Usually multi-destination flights are cheaper but there are some exceptions; you can run into some special discounts and cut-offs.
Have a nice trip, regards.
- (2008-08-05)
