Hotel costs were the pivotal factor in determining the most and least expensive cities on TripIndex: The cheapest average hotel room globally goes to Bangkok, at $81 per night – while at more than four times the cost, London rates are the most expensive, at $362 per night. The average cost of a room in the 10 cheapest global cities for hotels is $113, while the 10 most expensive destinations come in at an average of $262. The most affordable hotel room in the U.S. is in Las Vegas, where travelers can expect to pay $125. The most expensive room goes to Boston, coming in on the TripIndex at $354.