I stayed in Alex’s flat for a month, and I can honestly say it was the perfect choice. Almost everything is within walking distance, and for anything further away, the famous 28 tram stops right at the top of the road. There are supermarkets nearby and the flat itself is great.
The Wi-Fi is also really good- I had no problem on international video calls or uploading heavy files.
Alfama is also a beautiful section of the city, with lots of cute cafes and restaurants right on your doorstep.