Starting with the positives: if you want to be in Alfama/castello then the location is perfect with everything only a few minutes walk away. Communication and support from the host also was first class throughout.
However, the apartment looks very tired and desperately needs a refurbishment. Paint work is marked, silicone around sinks is mouldy etc. and there is a rather damp smell through out. The apartment was fairly clean but the chair covers in the dining area are badly stained and the rug is dirty and stained. If you are intending to cook please be aware that there are no basics (salt, sugar, oil) provided. There was no washing powder either. The outside area is essentially an interior space to let some light into the apartment block, gets no direct sunlight and is not a pleasant place to sit (cigarette ends on the floor).
This could be a fantastic Airbnb and the hosts were truly great but an upgrade is needed.