My parents had been living in Beijing under strict quarantine measures in the past few months and many tips from them can be helpful for the rest of the world. These measures worked for people there and if a city with close to 20 million people can control cases to not over 500, the rest of us can do it too.
Couriers: Couriers are lifelines of people in isolation. In Beijing, they drop packages at the curb in front of the building and people will come to pick theirs up. This could be done easily in Germany as many of us in metropolitan areas are living in apartment buildings and have the ability to open lobby entrance remotely. Instead of coming up and have face-to-face interaction. Couriers can drop all packages at the lobby after the entrance is opened remotely to reduce contact.
Clothing: Outside shoes and clothing need to be dis-infected or stored separately. My parents remind me that outside clothing also touch many surfaces and should be hung somewhere ventilated and shoes left outside of the door. This hasn't been done or mentioned outside of China.
Services and stores: In Beijing, many stores and services are done in open-air instead of an enclosed space. Merchandises were moved out to be sold. In banks, people line up outside and go in one by one to reduce contact and be in close distance with each other.