I could be wrong about this, but it seems to me that the 9.8 euros/sq.m. that appears to be recently imposed cap on rentals in Berlin is lower than the average rental price for housing in Prague 13 euros/sq.m. by my (hopefully straightforward) conversion of 340 CZK (reported in early 2019) or even the average rental price in Budapest, which I found reported to be 11 euros/sq.m. in 2017.
So, unless I'm mistaken with the figures, what justification was provided for having a cap on rental prices in Berlin that is lower than the average rental price in some Central & Eastern EU countries (where I'm guessing incomes are lower than in Berlin)?
Also note that there's another question asking in general terms why the measure was imposed. I'm asking here more precisely how the specific cap figure was justified by the proponents. (I've also noticed that the CDU, including Merkel, have spoken against this measure, but as far as I could find, as a matter of principle, not in terms of the cap figure.)