score:3
Nothing. Absolutely nothing.
EDIT: I have asked an older student and before the 1970s there was in fact
a so-called "Hörergeld" "listener money" which was in the range of 100-200 Mark (comparable to 30-45 $) for half a year.
The interesting thing is that is was not for the university, but for
the professor, so while there was charging, the answer is still correct.
I myself paid 120 Mark for half a year, but this gave me the right for
unlimited public transport in the area, so I did not count that.
The Hörergeld during the 1900s should have a comparable range (neglible
for wealthy students, perceptible to students working part time), because
Albert Einstein lamented that there was opposition to allow very poor
students listening to the courses.
This may come as a complete shock to people especially from the US but the concept of Universities charging their students was/is completely foreign in Germany. The running costs are paid by taxes from the government. There was always the firm belief in Germany that people have a right of education. This was so ingrained that students
Even worse:
In fact, I am one of the German students who did his "Diplom" with exactly this conditions. Now you may think that it may have changed, but you need only to read Mark Twains "A Tramp abroad" in the 1880s to see that it was the same in old times.
During the Bologna process starting nearly exactly with the beginning of the 21. century the old process was "reformed", changing Dipl. to Bachelor and Master and introducing charges as "Studiengebühren".
But due to problems with the organization and general disappointment with the system, "Studiengebühren" were mostly scrapped again.