Reachable from either Berlin-Schönefeld or Berlin-Tegel's airport, both 20 km away. I am at the far South of the city of Berlin, 1 km away from the border to Teltow. My home is comfortable for 4 people. The balcony overlooks a community garden so you'll have direct look on the trees during summer. There are two electric grill devices on the balcony so you can eat grilled food. There is also 1 long chair available on the balcony. My friends say my home is warm and inviting. And one home exchanger from Paris said it is "peaceful". There is a fan (ventilator) in the bedroom and the living room in case you would have an extremely hot summer which did not happen in a long time. The balcony offers space for 4-5 people so you can eat either outside or in the living room. A couple can sleep in the bedroom, 2 adults or children in the living room since the sofas are actually 2 real orthopedic beds, put together into a marocco-corner. I have 1 bicycle and you can use it. I am on the 3,5 floor with no lift. One gets used to it :-) There is a digital Roland piano with microphone for player and singer. Car swap might be a possibility.
I also have 2 cats since 09/2009. We can do pet care swap but not necessarily.
There are all kinds of shops (discount and non discount food stores, drugstore, pharmacy, clothes, 2 italian restaurants ...) in 300 and 500 meters walking distance so you do not depend on public transportation or car to go buy something.
The nearest big shopping mall is in Berlin-Steglitz, 5km far and easy to find, around 20/10 minutes bus/car.