Amazing little appartment. Walid and Joana were very friendly and helpful hosts. The flat is very cosy and has all amenities (fridge, stove etc), although we did not cook any meals. The little terrace is very enjoyable but does not offer much of a view.
Location is excellent, a little off the uber-touristy Rossio, with easy access to Estrela, Principe Real, Rossio neighborhood.
Tram 28 drives right past the door but is very crowded.
As others have noted, the Park rooftop bar is just across the street and can be heard pretty well. It can be a problem if you want to have an early night.