Octávio and Gi are fantastic hosts. They met us personally (with pastries) to show us the apartment and give us lots of helpful tips for our stay, including where to get the best ice cream and where the grocery store and bakery were. The apartment itself is spacious and comfortable, with two balconies and two bathrooms, and the location can't be beat. We were close enough to walk to almost everything we wanted to see in Lisbon, and there are great restaurants nearby. Even though the apartment is close to Lisbon's main attractions, the street itself is actually quite quiet and removed from the crowds and noise.
A few things to keep in mind: there are two sets of steep stairs in the apartment, there is no freezer attached to the fridge, and it can get chilly in the apartment. There are portable space heaters available, though.
We would definitely stay here again, and we recommend it to anyone wanting a nice, affordable apartment in Lisbon.