Which information do I have to insert at the address?
The address you set once while creating a new apartment. Afterwards you can not change it by yourself. Please fill in all the required data. If something does not apply to your apartment please just write 0 in the field.
Door number and stair are compuslory, but they are not shown online at your listing. They are just used internally for further functionalities of the website. Furthermore it is also for your own security that no third party can insert the same apartment with the same address.
If the system does not recognize the address (not the same spelling like in Google Maps) insert the address in Google Maps and then copy from there the correct spelling.