Traktor was a great host, very accommodating (we got in earlier than official check in, but he let us drop our bags in the apartment so we could make the most of our day in Berlin). Kreuzberg is a great location, very trendy, close to some great, very hip Berlin eateries and nightlife. Great Turkish restaurants close by. The rooms are very large, and the beds comfortable. Great for 3 couples or a group of friends. We would definitely return to Kreuzberg and this apartment. :)
There was tea and sugar and an Nespresso machine for coffee if you bring your own pods.
Very close to public transport. Not a really touristy area, which is great for exploring "real" Berlin. Highly recommended!