The assessor is typically an appointed official in each municipality and is obligated by New York State law to maintain assessments at a uniform percentage of market value each year. The assessor signs an oath to this effect when certifying the tentative assessment roll — the document containing each property assessment. The physical description (or inventory) and value estimate of every parcel is required to be kept current. In order to maintain a uniform roll, each year your assessor will need to analyze all of the properties in the municipality to determine which assessments need to be changed.
Typically, assessors serve for a designated period. In New York State this term is six years.
Before assessing any parcel of property, the assessor estimates its market value which is how much a property would sell for, in an open market, under normal conditions. To estimate market values, the assessor must be familiar with all aspects of the local real estate market.
A property’s value can be estimated in three different ways.
- Market Value:Â Â property is compared to others similar to it that have sold recently, using only sales where the buyer and seller both acted without undue pressure. normally used to value residential, vacant, and farm properties.
- Cost Value:  using current  labor and material prices, to replace the structure with a similar one. If the structure is not new, the assessor determines the depreciation since it was built. The resulting value is added to an estimate of the market value of the land.
- Income Value: how much income a property (like an apartment building, store, or factory) will produce if rented. Operating expenses, insurance, maintenance costs, financing terms, and how much money expected to be earned are considered. This method is called the income approach.
Assessors with computers can estimate values more efficiently than by hand. Computer Assisted Mass Appraisal (CAMA) techniques are used to analyze sales and estimate values for many properties at once.
Once the assessor estimates the market value of a property, its assessment is calculated. New York State law provides that all property within a municipality be assessed at a uniform percent of market value. The level of assessment can be five percent, 20 percent, 50 percent, or any other fraction, up to 100 percent. Everyone pays his or her fair share of taxes as long as every property in a locality is assessed at the same percent of value.
For example, a house with a market value of $100,000 located in a town that assesses 15 percent of value would have an assessment of $15,000.
