I'm offering a clean room located in Moabit which is 10 min. away from Tegel Airport and 15 mins to central station. Pretty much all you need is close by. Public transport such as the S-Bahn (Ringbahn) & various busses ( TXL which takes you to the airport) are within 3-5 min. walking distance.
You are more than welcome to use our living room as well. I am sharing this appartment with my 3 roommates who are students from Finland, Guatemala and Germany.
Bonus: we have a beautiful view over Berlin