While these sites say you can get a better deal if you combine your flight and hotel, most hotels come with a "Best Rate Guarantee," meaning if you can find a cheaper deal online, just give them a call and they will match it. Plus, you also get better customer service if you book directly through the hotel. I once checked into a hotel I booked using a travel app, and the hotel manager joked, "You booked on HotelTonight? We're going to give you the worst room." Get the full story at LifeHacker