It a lovely little quirky flat in the middle of buzzing Martim Moniz neighbourhood. Walking distance from pretty much all attractions (you need to expect to walk a lot of hills in Lisbon, so be prepared). 1min away from metro station and tram stop, close to good supermarkets. The flat is in a busy neighbourhood, so expect some noises in the evening, but it just adds to the atmosphere.
The flat itself is on a second floor with steep stairs (again very standard for old Lisbon), perfect for 2-3 people. It has all you need - bathroom, kitchen, two small bedrooms.
I would definitely consider staying again on my next trip.
Maria was very helpful and easy to deal with.