I (German citizen) have been accepted to a university in St Petersburg and would like to rent an apartment with my girlfriend (Russian citizen).
How does this work roughly? What paperwork will be necessary for this? We are looking for an apartment now and will contact the realtor who is offering it. What documents will I need to rent an apartment apart from my passport and study visa?
When I will have moved in, do I need to register in some government office? Since I am spending the majority of my time in Russia, will this apartment be my main residence [Hauptwohnsitz], or should this anyway remain in Germany, while I am registered in the Russian apartment as my second residence?