However, I have to say especially in metropolitan areas that even for hereditary leasehold a price is demanded that 50 km further away would almost count as a land price.
In metropolitan areas, the land price per square meter is also about 10 times higher than what has to be paid in rural areas. Quite simply: metropolitan area = expensive, dead land = cheap
Well, I hope that with a (in my opinion) secure job it will be possible for me to manage the arising costs over several decades. Of course, I wouldn’t just throw myself into something anywhere without equity... I believe this topic should (hopefully) at least be out of question from this aspect.
You should have equity regardless of the type of land ownership (full ownership, partial ownership, hereditary building right). If you cannot pay your loan, any ownership is gone (foreclosure).
What matters to me above all is that once everything is paid off and settled, the state doesn’t come along and think it has to lay a road straight through my garden or expropriate another plot for possible construction, whereby the profit merely ends up with the construction company and not in the true sense of an EXPROPRIATION; namely in the sense of the common good (which of course would also be annoying).
The probability is 0%. The hurdles are extremely high, and besides, you "only" lose land and house (regardless of the legal form) against payment of the market value. So no financial damage.
By the way, in cities and municipalities, a highway or railway line is not simply built through residential areas.
Especially with regard to the question about the different neighboring countries, it is important for me to find out where, for example, an expropriation — by whichever authority — is SIGNIFICANTLY harder to enforce.
The answer is simple. Under German law, you are probably the best-protected owner in the world. If somewhere in the world something is extensively regulated and it takes years to enforce things legally, then it’s Germany.
You know how slow everything is here since literally every little thing is regulated.
You should rather ask why many things are easier in many countries.
What do you actually want? To build, to buy, to satisfy curiosity? The meaning behind your considerations is not clear to me.