On arrival the receptionist said "Oh, sorry we don't have available King Bed, only two twin size beds"; when I got angry and told him: "That's your problem, I've made a booking and paid for a King size bed, so you must give me a King size bed room"... Magically, after 5min he said "I've found one for you"... Kinda tricky behaviour.
Not to mention that this was after they said "sorry I can't see in your booking that you have paid for the breakfast" when I did and it was explicitly mentioned in my booking + the Expedia/Hotels.com receipt.