Contract for a new tenant. What is necessary to include in?

[Konstantin Sobon]

Hey there,

I just acquired my first apartment in Germany (Cologne). 

My goal is to create some passive income with it and I want to take care of everything (being the Landlord). 

I am not sure how to create a contract for the tenant. Do you have any examples? Tips? Or template for me?

Like I am said I am from Germany and It would be awesome to hear your advise.

Best regards,

K