“The act or process of developing an opinion of value; an opinion of value. An appraisal must be numerically expressed as a specific amount, as a range of numbers or as a relationship (e.g. not more than, more than, not less than, less than) to a specified amount (SVP)
(noun) the act or process of developing an opinion of value, (adjective) of or pertaining to appraising and related functions such as appraisal practice or appraisal services. Comment: An appraisal must be numerically expressed as a specific amount, as a range of numbers, or as a relationship (e.g. nor or than, not less than) to a previous value opinion or numerical benchmark (e.g. assessed value collateral value) (USPAP, 2016-1017 ed.)”
Price per square foot is not a reliable way to determine your property's market value. This is a very general, often over relied upon approach that may give you an idea of what real estate trends are doing broadly, but is a poor source for figuring out what any individual property might command in an open market.
Price per square foot is a simple calculation for a more complex question: take the sale price and divide it by the square feet. This method ignores the facts of improvements of your home, quality, floor plan, location, etc. Unless you have an exact replica; this is not a reliable way to value a home.
Typically, the larger the sqft = price per sqft goes down. An appraisal takes into consideration the specific characteristics of your property (land and improvements), as well as research and we analyze sales of properties which would represent viable alternatives and appeal to similar buyers.
The (fee) appraised value is based on sales and listings of properties with similar characteristics dominant to each "subject" property as of an effective date (typically the date the property is inspected). Your property improvements are measured and viewed, inside and out, to determine the size, condition, quality and layout. An analysis of activity of recent and similar sales, along with available listings within the defined market area is completed to determine the market value of a your property.
Assessed value is based on general trends of a mass market segment within a defined market area as of an effective date (January 1 of every year). The trends of sales prior to the effective date will determine the assessed value placed on your property for the following year. In a broad sense, factors such as location, age, size, class/market grade (quality) are taken into consideration. The assessor usually does not go into your home; they have their designated area and do not have access to the interior of your home for individual improvements.