One has to distinguish two things: Is it about "office errors," meaning obviously wrongly recorded figures or other mistakes in processing? Or is it about fundamental weaknesses in the design of the regulations? When people file an objection, they receive a rejection notice after a few days, which among other things states that it is a standardized procedure in which there are no possibilities to take the special circumstances of the individual case into account. And I think that this is where the leverage lies to question the constitutionality.
In my opinion, it is not appropriate for a constitutional state if the same facts are treated completely differently in two different legal areas. At the back of the property, there would still be space to build a larger single-family house. The property is 2,000 square meters in size, we have a floor area ratio of 0.2, so actually 400 square meters could be built. My parents' house has a floor area of just under 100 square meters, and "my" house has a floor area of 130 square meters. Thus, in principle, another house could be built, even with a floor area of 170 square meters. But that’s not possible because the continuously built-up district ends directly behind the current buildings (there are garages). The rest is open land, so-called "marketable non-building land," which the valuation committee prices at 15 EUR. For the tax office, however, every square meter is worth 420 EUR.
If I were to apply for a building permit for this area because the tax office assesses it as building land, the city planning office would respond that it does not matter how the tax office sees it. And if you inform the tax office that the planning authority sees it as non-building land, it will reply that it doesn’t care.
We are far from uniformity of the law here.
And then, in my case, there is also the fact that there apparently is no way to find out in advance how the tax office would process the inheritance case, because it is not allowed to provide advice, but only processes specific tax cases concretely. And since no one knows how the tax office would handle this, no tax advisor is of any use to me either. Even if one had made a leasehold contract, there would still only be one single tax number in the future, by the way. I wonder how institutional leaseholders want to divide the new property tax among their leaseholders...
Matthias