Carolina's apartment packs a lot in; while it's not massive, the layout is clever (adults can sit outside a long way from sleeping children) and the renovation is very nice. We had 5 people in the apartment without feeling like we were squashed in. It was also spotless.
The location is convenient for a supermarket (Pingo), a bar with a view (Zambeze), and an elevator for getting up the hill. I recommend ambling down the hill to old Lisbon to get your bearings, and wearing sensible shoes. The castle is a must see and you'll hear the peacocks from the terrace of the apartment.
Carolina was responsive - especially when the light switch in the main hallway wasn't obvious to us! (It's the square plate to the left of the blue door outside the apartment).