I originally had a parking reservation at another location but my flight got cancelled at DCA and the next available flight was at BWI, i called the book2park representative, explained my situation (i had purchased the trip protection) & i was able to get my credit transferred to another parking location - BWI Westin. I am so appreciative of the service this business provides because those airport parking prices are ridiculous. I starting to travel more often than before and i will continue to use this service.