We spent in Lisbon 5 days, and We really enjoyed the stay at Maria's house, she was helpful and always friendly. The location is mega perfect, close to metro station (for connections to train station and airport), indian restaurant and market, and 20 minutes walk to city center.
The only issues we had was with very bad or no Wi-Fi in our room (but good connection in the kitchen) and high humidity in the room. If you like dogs, you will not have issues with Nina.
We recommend this place for any vacation!