site visit from an appraiser from the assessor's office. Depending on their internal practices or software limitations, their sq ft might not be exact (e.g.: Salt Lake County's appraisal software rounded only to nearest foot).

Sq ft is a major factor in valuation, but grade (type and quality of construction materials) and condition (either if updated or else how well-maintained the home is) contribute very significantly to the valuation and should not closely considered in the comps you might wish provide, if you appeal.

I've been a Hearing Officer for Salt Lake County tax appeals off and on since 1990, so I'm very familiar with the process and what typically does and doesn't work in property tax appeals. Ask away.