We spent a night in Aldina's apaprtmant but I think it is suitable for longer stay in Lisbon. It is in the suburb area, close to the airport (20 minutes walk, 10 minutes by bus) on the third floor in a three-storeyed house. It is clean, quiet (dispite the closeness of the airport). Aldina (and his son Rafael) is very kind and helpful host.
I recommend both.