Sofia's apartment is in a very central position. It's in a safe and quiet neighbourhood. It's got a small supermarket nearby and it's close to convenient bus stops, so that everything you want to visit in the city is easily reachable. The well known tram 28 is less than five minutes away!
The apartment has got enough space for two young and busy tourists, although I wouldn't recommend it if what you're looking for is space. Everything is quite tiny, especially the bathroom, which hasn't got a proper door, so forget privacy.
However, Sofia's place has got everything you need for a short getaway in Lisbon. Also, Sofia was always very available with us and answered all our questions kindly and promptly. I absolutely recommend staying at her place!