Anja and Christian's place is in a great location - close to lots of shopping and restaurants. There is a nearby metro stop that can bring you to the historical city center in 10-15 minutes. They were very helpful and responsive to any questions related to check in/out and allowed flexibility with timing which was a huge help. The apartment is small but equipped with everything you'll need. We enjoyed using the kitchen to cook breakfast and dinner. Overall a great way to visit Vienna and be close to all the sites without spending too much.