I looked it up.
If you look at the different language versions on Wikipedia several languages (like Italian, Dutch, Danish and Czech) also use the English term. It's a concept that has not really taken foot in Europe. It's mostly a North and South American thing (as well as Chinese and maybe a few other places with great wealth inequality). A handful of them exist for the rich and famous in a few places here, but it's the exception.
LOL, I also just googled "middle class home" in German and got a lot of local image results. But when I googled for "upper class home" in German suddenly the first 100 results or more were almost exclusively of American homes and with English text under them.
That got me thinking.
Not that we don't have a class system and social inequality, we most definitely do, but the social code around using those labels and how it presents in public is just different. A bit like the tall poppies thing in Australia or Jente's law in Scandinavia. You can be rich and powerful, but you're not allowed to display it too much. That would be vulgar.
I had to search for famous posh neighborhoods to get more reliably local results.
This is one of the poshest neighborhoods in the country (Hamburg Winterhude):
This is where the richest man in the country lives (co-owner of the ALDI supermarket chain) (in an otherwise irrelvant small town):
This is used to be the residence of the head of government when Bonn was still the capitol:
This is where former chancelor Schmidt lived until his death:
Former chancelor Kohl:
The first one in Bonn is deliberately simple and modern (at it's time) to signal the concept of modesty and transparency. The houses of Schmidt and Kohl were simly normal family homes, not even upper middle but middle middle class from the looks of it.
Don't let the relative simplicity fool you though. This one was the most expensive house offered for sale in Germany in 2024 - the asking price is 17.6 million dollars and it's on the posh island of Sylt:
Location clearly matters.
This one in Munich was sold for 30 million a while ago and used to belong to the manager of Goldman Sachs (to be fair, long before that it used to belong to Nobel laureate Thomas Mann, so that likely played a role in the pricing):