You're traveling to Vienna and aren't really sure of how it all works. You see a bunch of different listings, and they all look the same. Ludwig's is the best:
1) The Location is 6 stars out of five. Everything in city center is walking distance, the subway is a block away, and there is a full on grocery store ~100 meters from the front door.
2) It has air conditioning. Most other places will not have that.
3) Ludwig was very good about check in - meeting us at the door and making sure we got set up okay after ~20 hours of travel. Especially useful in our exhausted condition.