We stayed for a week for our honeymoon in Ana's apartment and we absolutely loved it ! Highly recommend it, we will be back :-)
The area first of all, Graça, is very lively with many shops, cafes and a little shopping centre to get all your grocery 2 minutes walking from the flat. You also have the 2 observatory points within 5 minutes walk to get great views of the city.
The apartment is in top conditions, very clean, on the top floor with good views. It's very spacious, especially for 2 people. Very secure as well. We had a rented car and got to use the underground parking : it's very secure as well, plenty of space, the building is quite new with good standards.
It's very convenient to go to the airport or outside of town. We found ourselves walking to town (downhill, about 10-15 minutes walk from the main squares/Bairro Alto etc...) and got Ubers back to the flat. We also used the tram 28 line which is literally outside the building.
And last but not least, our host Ana : from the very start up until check out, Ana was very responsive and kind. She gave us plenty of information regarding the area and places to go, made sure we got in the place safely, and we couldn't be thankful enough because it really helped us relax and have a fantastic time in Lisbon !
We will be back to Lisbon and we will get in touch with Ana to stay here again :-)