[lhopki01]

Had a quick look at the map and it seems Ober-Erlenbach to other other side of Bad Homburg is only 10km. That's not even a half hour cycle for an adult.

It also looks like Ober-Erlenbach and Nieder-Erlenbach are the only two villages and twos around Frankfurt that don't have a train station to Frankfurt.

Almost every reason I've ever seen given for needing a car have to do with deciding to live somewhere with terrible public transport or lack of public infrastructure nearby.