Great location, on a pedestrian street (a "Calcada" with lots of stairs) above the center of the city. Right out the from door was was a nice view of the castle, across the valley on the next of Lisbon's Seven Hillls.
Many excellent restaurants in easy walking distance; every meal was great. And that includes the breakfasts delivered by Luis' team each morning. Luis took some of his guests (including us) to a wine bar one night, which we really enjoyed. Some went on from there to a Fado show, until 2am.

The interior of the apartment was nice finished and well equipped. With the windows open and the restuarant downstairs, it could be nosy, but with windows closed (turn on the A/C in summer), very little street noise (and no cars). the windows were good people-watching locations.
When we return to Lisbon, we[ll try to stay here again.