If you have to do researches in Munich city it will be important to do some researches before you'll go there.
I know that in Munich there are four or five archives which could have documents which could be important for you.
There are also some online archives where different kinds of documents from Munich city are available online.
Most important for my own researches were the "Gedenkbuch der Münchner Juden" and the Arolsen Archives.
But there are also the city directories, lists of students of the university and army records of WWI available online.
The Stadtarchiv, the Berzirksarchiv and the Staatsarchiv do have some more records which could be important for you.
Corinne Iten, Switzerland