Which of the following is not considered a reliable data source for property information?

The selection indicating that informal surveys are not considered a reliable data source for property information is accurate. Informal surveys often involve anecdotal evidence or subjective opinions rather than systematic collection of data vetted through professional standards. This lack of rigor makes them less dependable when it comes to making informed property assessments.

In contrast, licensed professionals, assessors, and engineers typically utilize standardized methods and established practices to gather and analyze property data. Licensed professionals, such as real estate agents or appraisers, bring a level of expertise and adherence to guidelines that ensures data quality. Assessors are tasked with evaluating property values using comprehensive methodologies, which are usually grounded in legally established criteria. Engineers contribute technical insights based on empirical data and design standards, making their input reliable for evaluating physical property conditions.

Ultimately, while informal surveys may provide some insights or collect opinions from individuals, they fail to meet the reliability standards imposed by the other sources, making them unsuitable for thorough property evaluation.