General data, which affect values on national, state / regional, or neighborhood levels.
Specific data, about the site, title, and improvements of the property.
Comparative data, which regards recent sales, cost, and income information for similar properties.
General Data
Trends in business cycles, the economy, financing options, population, price levels, building costs, purchasing power and tax rates
Physical factors affecting value
The most important of these is location
Others are size, topography, appearance, lot size/shape, street pattern, soil and subsoil conditions, drainage, hazards, climate, utilities, nuisances, conformity of improvements, and proximity to supporting facilities
Economic factors such as population levels, balance of land use, vacant land, new construction, price and rent levels, vacancy rates, lender attitudes, utility costs, insurance rates, wage levels, and transportation systems
Governmental factors such as municipal services, planning and zoning, building codes, development regulations, taxes, special assessments, and services
Social factors such as population density, crime rate, income levels, labor supply and skill levels, and cultural activities available
The economic and general background information needed for development of an accurate property tax appraisal may often be beyond the resources of a county assessor's staff
The use of the computer has increased availability of historical and statistical data related to appraisals
Statistical analysis of large amounts of data using techniques like multiple regression analysis permit the development of valuation factors which can substitute for some of the data described above
Specific Data
Ownership data, including owner's identity, type of ownership (warranty deed, titling information, etc.) easements or encroachments, zoning regulations, assessed value and taxes, and deed restrictions and covenants
Site information, including a description of the land (size, shape, topography, and location) and public improvements (paving, walks, curbs, sewers, utilities)
Corner influence, building orientation, accessibility of the site, and any advertising value offered by the site are also considered
Data collected for an industrial or commercial property may be very different from that needed to appraise a single-family residence
Improvement information such as the size, quality and condition of all buildings and physical improvements, along with an analysis of their layout, style, and design
A clear statement about the current use of the property should also be included
If multiple uses exist, they should be noted and documented as carefully as possible
Comparative Data
Cost data, which may be obtained through developers and general contractors
Many governments use Marshall Swift - a private firm that studies and develops costs for markets across the country
The cost data may also be used as historical cost for individual properties and as a basis for developing up-to-date factor tables to make historical costs current
Sales data, which is collected and basic adjustments, are developed, such as time and location, as well as adjustments for different property characteristics
As a result, benchmark properties for comparison purposes are established
Income data, which is gathered from income and expense statements
The assessor may develop economic rents, vacancy and collection loss allowances, discount, and effective tax and recapture rates