I had a great time at Filipa & Diogo's place - a newly renovated and furnished spacious apartment with a large terrace to sit and enjoy the sunshine. The apartment offers everything you need and is well-equipped and in a good location next to Alfama and Mouraria. Do bring ear-plugs though when you are sensitive to noise, as you will hear the trains.
Diogo & Filipa were very good hosts and giving me tips on things to do and places to be and I really loved their recommendation for a Fado place in Alfama - was a great experience!