Dissatisfied guests at a Hilton Garden Inn in downtown Austin, Texas, have reviewed the hotel as “very run down” and “janky,” in reference to faulty elevators. One guest said the beds were “rock hard,” and another called the place “a complete nightmare from start to finish.” That is a big reason the new owner decided to buy it. The hotel is one of many around the U.S. that have languished for years in need of a refresh but whose operators have struggled to find the cash to pull off the renovations. Now, as prices decline and the number of new…