All good points there. I don’t know if an ad valorem tax is unconstitutional if it is assessed at the local or state level, but I agree that this is not a good way to raise tax revenue. I’ve long said that the ideal method of property taxation would be based on physical characteristics of the property, not the value. In the case of residential real estate, the taxes should be assessed based on the size of the lot, the number of bedrooms in the house, the size of the structure, etc. These are the things that are usually the best indicators of the property owner’s impacts on public services.
Local governments are bound by the constitution’s prohibition against deprivation of property. A crime must first be proven.