Many land value taxes are in fact based only on unimproved property value. The main problem is estimating that value, but it’s not really a very difficult problem in practice. The usual solution is to have a valuation office independent from the tax office, and subject to an appeal process where there is evidence that the valuation was incorrect.
It’s not an elegant solution, but it seems much less likely to distort incentives than including power over improvements in the land value.
Many land value taxes are in fact based only on unimproved property value. The main problem is estimating that value, but it’s not really a very difficult problem in practice. The usual solution is to have a valuation office independent from the tax office, and subject to an appeal process where there is evidence that the valuation was incorrect.
It’s not an elegant solution, but it seems much less likely to distort incentives than including power over improvements in the land value.