Fair Market Value-the price for property which would be agreed upon between a willing and informed buyer and a willing and informed seller under usual and ordinary circumstances; it shall be the highest price estimated in terms of money which property will bring if exposed for sale on the open market with reasonable time allowed to find a purchaser who is buying with knowledge of all the uses and purposes to which the property is best adapted and for which it can be legally used.
La. Admin. Code tit. 61, § V-109