I'm a resident in Germany and I live in a WG room (‘flat share’). My girlfriend is applying for a visitor visa to come to Germany. I'll be giving her an informal invitation letter with my required documents.
I want to know if there is any kind of official letter (which I can get from Rathaus) necessary for hosting a person?
As I live in a WG room and she will be obviously staying with me, I want to know that is there any requirement of the area of the room for two people to live in??