Great apartment in a top notch location. Terreiro do Paço, Rua Augusta and the downtown are within walkable distance.
Mauro was a great host, quickly responding and always doing his best to accommodate our requests.
One particularly positive thing that has to be mentioned is the heating. We stayed in the apartment during the coldest months (Jan and Feb) with a 8 year old and a 2 months old. The heating in this place allowed us to be comfortable every single day, sometimes even feeling too hot and having to dial the heater down. Inside the flat, we dressed as if it was summer. This is not common at all in Lisbon (at least from our experience) as the apartments are usually cold.
Great stay. Highly recommended!