State law requires that your property be assessed at market value. Market value is the amount a typical, well informed purchaser would be willing to pay for a property. For a sale to be a market value (arms-length or qualified) sale, the seller and buyer must be unrelated, the seller must be willing (but not under pressure) to buy, the property must be on the market for a reasonable length of time, the payment must be in cash or equivalent, and the financing must be typical for that type of property.
Fair cash value has been determined by the Massachusetts Supreme Judicial Court as ”fair market value” which is the price an owner willing but not under compulsion to sell ought to receive from one willing but not under compulsion to buy. It means the highest price that a normal purchaser not under peculiar compulsion will pay at the time, and cannot exceed the sum that the owner after reasonable effort could obtain for this property. A valuation (price) limited to what the property is worth to the purchaser is not market value. The fair cash value is the value the property would have on January first or any taxable year in the hands of any owner, including the present owner. (Boston Gas Co. v. Assessors of Boston, 334 Mass. 549, 566 (1956).