Wow. I have had some nice flats on AirBnB, but this one really impressed me.
The stairs are a hard climb, but if that doesn't turn you away, then consider giving Jorge's (George) place a try. The flat is lovely, and impressively fits a lot of room into a small space. The kitchen was handy, the balconies were appreciated, my wife breathed a sigh of relief when she saw the hair dryer and clothes-iron, and my 2 year old loved the little side library room.
Everything you could want, for a good price, only 10 minutes walk from Chiado, and equally close to the train station.
Manuel and Jorge made our stay easy, comfortable and helped us with our arrival and departure.