We stayed one night, while we were layed over in Lisbon. Ruben was very kind, and personally greeted us on arrival, even though it was very late at night. We were able to walk to the apartment from the airport, and it cost us only 3 euros to take an Uber back the next day.
The apartment itself is set up like a hostel. There are 3 bedrooms (all for guests), and a shared kitchen and bathroom. Unfortunately, given the small space, we heard a lot of noise from the other guests early in the morning. The bedroom is small but it has everything you need (clean sheets, dresser, lock on the door). The bed was very very firm - almost like sleeping on the floor, so we got little sleep.
Breakfast was simple (cereal, fruits) but much appreciated.
All in all, it was fine for one night and we enjoyed our brief encounter with Ruben. It's proximity to the airport is definitely a bonus! We would stay here longer, if there was a different mattress.