That's what I did when we moved to Berlin/Germany: Sold my car. My wife has the only car in the house.
I have joined two carsharing services in case I need a car - one of them DriveNow as in the article. But that occasion pops up far fewer times than I originally thought.
There is no guarantee to have a car nearby but usually there is one down the street. The iPhone app works great to locate the cars and provides a filter in case I want a specific model (do prefer the Mini).