[gopher_space]

Off the top of my head: value is tied to appraisal which happens during a sale. Land values wouldn't change to reflect local demand and this could depress tax revenue. You'd probably be able to get away with some foolishness regarding the building condition.

[lotsofpulp]

This is only true for very few markets that have ridiculous subsidies for land owners via laws that limit property tax, such as California.

Most other places re-assess all property values on an ongoing basis and charge you accordingly.

[mixdup]

>Most other places re-assess all property values on an ongoing basis and charge you accordingly

Those reassessments are based on market activity over the preceding year. Property changing hands without actually being a real estate transaction does not generate market data for the assessors to use