Which category of adjustment is NOT essential when preparing a market data estimate of value?

When preparing a market data estimate of value, the inclusion of recent sales of comparable properties, current market conditions, and property upgrades or renovations is essential for accuracy. These factors directly influence a property's market value and help establish a more precise estimate.

However, the original cost of the building is not a necessary adjustment in this context. This cost reflects what was paid to acquire or construct the building and does not take into account the fluctuations in market demand, changes in the neighborhood, or improvements made to the property. Market value is determined by what buyers are willing to pay for similar properties at the current time, rather than historical costs. Thus, focusing on the current market dynamics and comparable sales provides a more relevant basis for price estimation.