What does an appraisal based on an extraordinary assumption include?

An appraisal based on an extraordinary assumption includes a condition that is assumed to be true and is supported by some evidence. This type of assumption is made when there are specific circumstances that might affect the valuation but cannot be directly observed or confirmed. The appraiser relies on the belief that the given condition holds true based on available data or reasoning, rather than taking it for granted or basing it purely on conjecture.

Such assumptions are crucial in situations where the appraiser requires a hypothetical scenario to arrive at a value estimate, like in cases where a property is non-typical or when certain information is missing. This differs significantly from the other options which imply a lack of evidence or reliance on subjective opinion, which do not hold the same rigorous standard of support and verification that an extraordinary assumption must adhere to.