We stayed at Benjamin's place for 4 nights while exploring Lisbon. It is a small, very basic apartment - but if you plan on spending a lot of time out and about then it's sufficient. It's in a great location in Alfama, close to one of the most beautiful viewpoints, Tram 28 stops, and a few mini-marts. We walked most places or took the tram. As a host, Benjamin was easy to communicate with and accommodated our early arrival. Plus, he gave us some tips that came in handy throughout our visit!
Overall, it was a functional, no-frills place for our visit. A few things to note: Steep stairs to get to the apartment so if you have bad knees, beware. If you're looking for nightlife, Alfama is not for you; you're probably better off in Barrio Alto. There was construction right next to the apartment when we were there - it was very noisy during the day (but nothing at night). No AC (as noted in the listing), but it wasn't too much of an issue for us even in early September when it was pretty warm.