We stayed at Duarte & Joana's place for 4 days during our trip through Portugal and we really had a great time in Lisboa.
The communication was very easy and they provided us with all the information necessary. When we arrived at the apartment we were welcomed by a goof friend of them and everything was very friendly.
The apartment is just like described and seen in the pictures. It is very clean and comfortable and perfect for your stay in Lisboa.
The place is in the heart of Portugal and you can very easily get anywhere by foot. There are a lot of cool restaurants, cafes and bars around and the metro is only 10 minutes away.
We definitely recommend this place, we had an awesome time!