Location: Van Nuys, CA
Solution: Taxes are based on the assessed value of your home as determined by the local tax assessor. Tom has already appealed to his tax assessor, so his next step would be appealing to the county board of equalization. California has a guide to residential property assessment appeals. New York has one too, called a guide to fair assessments. Search online for one in your state.
If Tom’s house is, as he believes, being assessed at a higher market value than nearby homes of similar size and value, he should ask for “comps” from real estate broker showing the value of these surrounding properties. Having paperwork to back up your point always helps.
Tom might also consider calling the California Taxpayers’ Association, which aims to protect taxpayers from unnecessary taxes. Many states have similar organizations. To find them Google your state + taxpayers association.