This is a lovely place to stay!
It is clean and nicely set out. It has a nice bathroom up on the same floor as the bedroom and also a small room for keeping your clothes with a place to iron if you want to freshen up your things. The bed is sooo comfortable and there is a sweet little balcony with a nice view. Downstairs is a good little kitchen area, complete with dishwasher and washing machine. There is also a downstairs toilet which is great because you don't have to keep nipping up and down stairs all the time.
The location is really good - restaurants, cafes and food shops nearby. It is possible to walk to almost any part of the city from the apartment - also very central for all transport (including the Tram #28). The Castelo de Sao Jorge is close by as is Alfama. Plus it is a short walk to the sea-front.
Our host, Sarah, and her partner Tahil were so pleasant and helpful; always replied quickly to our emails and on-site to answer questions and make recommendations when you are there (they live in the same small apartment block).
We really loved it and will be recommending it to all our friends!