The apartment is good and very centrally located in the Barrio Alto.
The host, Tomás, is very kind.
It is an attic, so the noises from the streets around (that are full of people during the night) got very attenuated, but not completely.
The attic is very good, a full kitchen with kettle is available and a private bathroom with shower.
It's a bit warm during summer and I'm pretty sure that there's no air-conditioning.
Keeping the windows open during the night it's not a great solution due to all the people in the restaurants and venues below, so this particular should be taken into account if you will visit Lisbon during very hot days.