Housing size. A 2 bedroom house in The New World is nothing like a 2 bedroom place in Europe. I bet the Berlin housing is a LOT smaller than a US place.
Even in SF, the housing is a lot larger than almost all of Europe. London is a disaster if you expect much if any space.
Agreed about London vs. the US, and the same would hold for Paris, but Berlin is the exception: apartments (and expectations) are huge compared to any other capital city.
I'm not sure why that is. Being physically cut off from the world helped keep prices down for sure, but it doesn't explain why apartments are large relative to the number of bedrooms.
Even in SF, the housing is a lot larger than almost all of Europe. London is a disaster if you expect much if any space.