Additionally the banks do not want to use negative credit rates ever, or any effectively close to zero. Therefore if prices for building the houses are too hig

Additionally the banks do not want to use negative credit rates ever, or any effectively close to zero. Therefore if prices for building the houses are too high, they cannot bring them down. What they can only do is repossess, and that cannot bring the price down by much either. The situation is further complicated for the costs incurred for the maintenance of the buildings and general land tax - but that should theoretically push developers to make condos. But even those are getting too expensive.