We would recommend everybody to stay at Ronald's place. It is located very conveniently in between the station (Santa Justa) and the city center. If you do not mind walking, almost everything can be done and reached within 15 - 20 minutes. The place was very clean and just big enough for the two of us. Unfortunately, because we stayed for 5 days we managed to build up quite a heap of trash. Of course, this is not Ronald's fault and maybe we should have thrown it away outside but we hope he did not mind too much.
Furthermore, Ronald communicated very well and very quickly, he also had some great recommendations for food and activities. All in all, great experience and well recommended.