That's not enough for me to sugarcoat 120sqm as a maximum limit when people who have never contributed anything to Germany can live for free with 3 children in large apartments..
The goal here is to support families who can no longer afford it, so the approach is correct. Because anyone who can afford 140m2 or more really doesn't need this support.
Regarding terrace and living space, it first counts only as 50%, and what if it suddenly becomes larger after 1-2 years?
Oh, and when I look around in our residential area, everyone who built 140-150m2 without a basement has misused the garage as storage space, so you could in turn say how can anyone build without a basement...
or how can anyone build with a knee wall, etc.