Alexandra was a brilliant host and pointed out all the local places for us to get cash and supplies for the flat as well as a few places to eat. Her english is excellent as well for those traveling and can't speak German.
The flat has loads of room and is perfect for anyone going with a larger group or with friends who are not coupled. The billiards/pool room in the basement is a brilliant touch and the 2 bathrooms are excellent and very clean, it has one of the best showers I have used and far far better than most hotels.
Public transport links are everywhere but you don't have to travel far to find cafes, bars and nightclubs and everyone in Berlin was very friendly.
If you get a Welcome to Berlin travel card at the airport you can use the public transport for the whole duration and its easy to get from the airport to the flat via this.
Traveling time from the airport to the flat will be around 1 hour with around 6-8 minutes of walking when at the last station.