Is it reasonable to calculate construction costs by cubic meter in a gallery?

Of course you can buy a house from the North, but there are no reasonable providers there. However, the price difference is probably more in the building plot. I don’t believe you can get the m² for 18 € in Bavaria. In rural (emergency) areas in Lower Saxony, however, this is quite common. If you want a gallery, you must not ask about costs and utility value. Beautiful things just cost money.