We spent 8 days in João's apartment. Although we didnt meet him in person, he was very helpful and gave us all the info we needed.
About the apartment:
+ very good location in Alfama right next to the castle
+ Bus stop 2 min. walking
+ safe, clean and charming interior
+ welcome drinks (wine+ selfmade ginja, def. a must try in Lisboa)
+ great communication with João and Silvia, they will give tips for your stay and offer help when needed.
+ totally safe area, its crowded but pretty quiet at night (we stayed in February)
- The only small downside might be the amount of sunlight in the apartment. On the other hand the lighting inside is very well done and it gives you a cozy feeling! And I guess during summer its great, because it wont heat up that much.
All in all we had a great time here and would always choose João's place again for future visits :)