Prior to arriving communication with Antonio was good, and he was very helpful in sending a detailed list of places to visit.
Flat itself was a really nice, compact apartment, with everything me and my girlfriend needed for our weekend stay. Clean and comfortable. It's in a great location (10minutes walk from metro) but also very walkable to a lot of the major sights (Catedral de la Almudena/ Royal Palace, Reina Sofia Museum etc).
Would definitely recommend staying here and would return if visiting Madrid again.