A very nice place to stay. Nothing to add to the previous reviews, really. The apt is in old building but freshly painted walls, very clean, tastefully decorated. If staying during winter: no central heating but there are two electric radiators and the towel dryer in the bathroom seems to heat enough the bathroom pretty well. My wife is super sensitive to cold but she seemed fine. The kitchen is very well equipped if you're up for cooking your own dinner (we never bothered to do that though as there are so many relatively cheap and nice places to eat in the area). The living room doesn't get much daylight - but again we were out exploring Lisbon until late so that wasn't an issue. All of the above are the only (very minor, obviously) observations I'd say you might consider. All in all - it's an amazing place to stay, lovely terrace by the way, we absolutely loved it and I'm already recommending it to all my friends.
The neighborhood was perfect (for us) - it's not too touristy, a few very cool local spots right around the corner plus two very hip cafes and max 10 mins walk to the more touristy part. We enjoy walking and have walked everywhere.