Even with all the airfare and hotel rate comparison sites out there, it's almost impossible to know whether you are really getting the best possible price. 

Enter Intercontinental Hotels Group (IHG), the parent company of Crowne Plaza and Holiday Inn, which just announced a bold new initiative on all of its hotel websites: the "Best Price Guarantee." 

Beginning this week, IHG's "Best Price Guarantee" stipulates that "any guest who finds a qualifying, lower room price for an IHG hotel elsewhere online will receive their first night free, and the rest of their stay will match the price found." 

IHG is also calling this initiative the "Book with Us Advantage," hoping to attract customers to their own hotel websites and away from large booking sites like Expedia and Kayak. IHG also promises that booking a hotel directly through its respective website is a safe and secure transaction, has no hidden booking fees, and earns guests award points in the Priority Club Rewards hotel loyalty program. 

To kick-start the "Best Price Guarantee" initiative, IHG announced it is also running a Twitter contest.

Beginning Sept. 20 through Sept. 24, IHG will be giving away 250 free hotel room nights. 

To enter, you must follow @PriorityClub on Twitter and tweet an answer to the question: "What would you do with a free night?" using the hashtag #BestPriceGuarantee. 

IHG will award 50 free hotel room nights each day of the contest. (For those who aren't on Twitter, you can enter here

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