We stayed at Sonia and Miguel's place for 4 nights. We arrived from the airport and found the place very easily, it's a very short walk from Trinidade metro station. Miguel let us in and showed us around and was very welcoming.
The apartment itself was very comfortable and looked just like what we expected from the photos. It's within walking distance of the main areas, so although it's close to the metro, the only time we used the metro was getting to and from the airport.
Miguel works in the store underneath the apartment, so although we didn't have any issues during our stay, he would have been easy to find if we had needed anything.
We didn't generally have a noise problem in the flat, but one night there was very heavy rain and it was very loud in the flat. If you have rain forecast on your trip, and you're a light sleeper, I'd advise earplugs!
All in all we had a lovely stay at great value and I'd highly recommend Miguel and Sonia's place to others.