We had a nice stay at this apartment. It was clean and cozy. The communication with the host was great and luggage storage was also really easy.
The two downsides for us were: The stairs that lead up to the apartment are really narrow and steep so it was tough getting the luggage upstairs. And the whole house was really noisy. Every bit of floor is squeaky and the door especially is really loud.
I would still recommend if you want a cozy place in the center of Lisbon!