The tax “value” is effectively meaningless when considering a potential sale price.
First off, they are set at a certain point in time and don’t fluctuate like real values do.
Second, they are set to merely be used as a base for property tax assessments.
Third, there is no reason to make them exactly match the actual value as the intent is to find relevance between one property vs another.
Fourth, it’s much easier to set the assessed values much lower than the actuals. The bureaucracy doesn’t want to fight everyone about their assessment, so using a formula that sets assessed substantially lower than actual keeps people from complaining. If you’re assessed at $500k and it’s been for sale for a long period of time at $500k there will be lawsuits. If you assess that same property at $250k they can’t complain as much.
Property tax BILLS are calculated by taking the assessed value times the mill rate. If you double the assessed value and halve the mill rate (and vice-versa), the tax bill would be the same.
You’re not telling me anything I don’t already know, but good summary