The true villain in this story is the home inspector who was incompetent enough to miss a decommissioned upfeed hot-water heating system, a sure indicator of the presence of elemental mercury in the home.
Home inspectors are by and large useless. They exist because the laws say they must exist, but they don't have a strong regulatory body making sure that they're competent. Once the house is sold they're gone.
For the most part they're just yet another guy who takes a cut whenever a house is sold.
