What is the term for an estimate of value, usually in writing, of an adequately described property as of a given date?

The term that accurately describes an estimate of value, usually documented in writing, for adequately described property as of a given date is "appraisal." An appraisal is a formal process conducted by a qualified appraiser who assesses the value of a property based on a variety of factors, including market trends, property condition, and comparable sales. This process results in a comprehensive report that provides a qualified opinion on the property's value at a specific point in time.

The other terms do not capture this specific meaning as effectively. Assessment typically refers to the determination of property value for taxation purposes and may not include a detailed analysis or written documentation as formal as an appraisal. Estimation is a more general term that can refer to a rough calculation or judgment about value, lacking the specificity and formalization of an appraisal. Valuation is often used interchangeably with appraisal but is a broader concept that can apply to various contexts beyond real estate, potentially lacking the formal, written aspect that defines an appraisal.