We had a good time at Nuno and his friends apartment. The check-in went super smooth, the communication was outstandingly good. The apartment itself looks exactly as pictured: very minimalistic interior, with all facilities that you need. I personally would not recommend staying here with more than 3 people as the apartment is not too big. As the staircase is steep and narrow, I also would not recommend staying here if you are older, have mobility issues or come with heavy luggage.
The beds are very comfy (can't speak for the sleeping couch) and we slept like babies - but: there are some major building workings going on right next to the house which do not seem to be finished any time soon (they start at 8am except on sundays and end at about 7pm). If you are an early bird like us or do not plan to spend too much time at the apartment, this should be no problem, otherwise this would be a point to consider.
The area is an adventure in itself: charming old houses next to ruins, super winding streets, major slopes, clotheslines in front of the window. Some famous and really good Portuguese restaurants (with Fado music) as well as small bars are located just a stone's throw away. Also there are several mini markets round the corner.
Even though Lisbon is a walking friendly city, the public transport connections from 5 minutes away Martim Moniz (metro, bus and tram) are excellent.
All in all we had a nice time in this place. The Portuguese people are extraordinary friendly and hospitable - we felt very welcome in the apartment, city and country and will definitely be back. Thanks for having us!