Myself and my ten year old had a wonderful eight days in Marta's place, which we found to be comfortable, fun and full of character! The apartment was a beautiful fusion of traditional Portuguese and modern, and my son loved the bed space in the living room (which is definitely big enough to accommodate a small adult)! This was a working trip, so the lovely desk space was appreciated. I didn't find the lack of wardrobe problematic, but can see how it might be for some.
Marta was an excellent host, checking in by text to make sure things were fine and easily available to answer any queries- though everything went very smoothly.
For us, the location slightly outside of the centre was perfect. Trams and buses are extremely frequent, with all the sights just a short ride away. The proximity to the LX Factory makes things a little noisy from time to time, but its also a benefit to have it nearby with its nice bars and restaurants. Its also a quick to Belem- would recommend the amazing restaurant Este Oeste, with fabulous views of the river and gorgeous food! We are in Lisbon regularly, and this is the nicest place we've stayed so far- we'll definitely be back.