It's far from the turistic center. Like 1h walking in a straight line (with nice view, though, by the Tejo river). A few meters along the sidewalk there's a little coffee/restaurante where you can taste a tipical portuguese meal for 7/8 euros (ask for the "menu". Thats Include the meal, a drink, the dessert and a coffee.
The apartment is flawless. Very comfortable, silent, illuminated, clean, great shower, great equipped kitchen and great fluffly chairs (thats was very helpful because I had to work there). The inclined roof and the little inner balcony its a charm. I always had my breakfast there, looking to the street through the windows.
The hosts were attentive and always available since the first contact. Definitively a positive experience. :)