4.2.1.3. Willing and Reasonably Knowledgeable Buyers and Sellers.Willing and reasonably knowledgeable buyers and sellers are not defined as all-knowing, but rather as having the knowledge possessed by the “typical ‘willing buyer-willing seller’” in the marketplace.220 An arm’s-length transaction cannot be disregarded solely because a buyer or seller lacked “perfect” knowledge.221 For example, the Federal Circuit held that it was appropriate to consider “a relevant market made up of investors who are real but are speculating in whole or major part.”222 And as the same court held in a later appeal, “uncontroverted evidence of an active real estate market compels the conclusion that the typical ‘willing buyer-willing seller’ requirement of fair market value had been met . . . .”223 As a result, “[w]hile an [appraiser] might be justified in adjusting the fair market value figure by discarding aberrational values based upon sales between related entities or fraudulent sales . . . , an [appraiser] may not discard an entire market as aberrational.”224 

The hypothetical buyer and seller under the federal definition of market value are objective market participants, motivated by typical market considerations: “[T]he same considerations are to be regarded as in the sale of property between private parties[,]”225 having regard for “the existing business or wants of the community . . . .”226 As the Supreme Court warned, “care must be taken to avoid . . . supposing the hypothetical purchaser to have either the same idiosyncrasies as the owner, or the same opportunities for use of the property as a taker armed with the power of eminent domain.”227