We stayed in Mata's apartment for 1 week with our 8-month old son. The pictures here don't really do justice to this amazing place, which felt like a home-away-from-home right away. Everything we needed was available. Mata was even so kind to provide us with a high chair and a travel cod.
The neighbourhood is really nice with shops, restaurants and everything on walking distance. Subway and tram are also nearby so you can easily visit all of Berlin. We had our bikes with us which was also convenient to do some sightseeing in bike-friendly Berlin.
To summarize: great place, great location, great owner, would totally recommend.