This apartment is great: very well located (less than 10 minute walks from museums and opera), quite well isolated because it is in quite a lively area, with a lot of space! There are great places to store your clothes, it is very nice to stay there.
Communication was great at almost all times (with a lot of great recommandations to eat around), except a few hours upon arrival. The host told us we would be able to check in around noon, but at noon until 3PM, nobody answered anymore. But if you need to store your luggage and come from the airport via the CAT train, there are free lockers over there, so there are easy solutions 😊
Again, I would 100% recommend staying there to enjoy Vienna at its best!