Taxes, Valuing Property
For purposes of taxation, the fair market value of all property that is a part of the decedent's estate must be established.  "Fair market value" is the price a willing buyer would pay a willing seller when both parties know all of the facts necessary to evaluate the object's worth.

Fair market value must be established as it existed on the day of death.  It is the personal representative's duty to establish these values, which must then be reported to the Register of Wills as an itemized list known as an Inventory. A professional appraiser may be hired to assist with this task, whose fees are charged to the estate as an administrative expense.  Typically, the fair market value will simply be reported as the value received for the property when it is sold.

See: Pennsylvania Inheritance Tax, Generally; Federal Estate Tax, Generally