In my state, you need to get an independent appraisal, which then is used to protest what the taxing body wants to claim.
Tax authorities are not required to care about your unsubstantiated thoughts of value.
Tax authorities should be required by lay, and maybe even their own conscience, to give an honest appraisal of the property -— IF he thinks the property is worth $40,000, it should be appraised for $40,000 for tax purposes.
That’s correct. He needs an appraisal by a state or organizational certified appraiser.
Then challenge the assessor’s certification (most likely none) and thus the assessment.