The City of Champaign Township held a special study session Tuesday night after its monthly meeting to address property tax assessments, a popular concern of Champaign taxpayers after the higher 2007 tax rate was approved by the City Council last month.

Property tax assessments, which are determined by the township assessor, are used to calculate how much a property owner will have to pay in property taxes.

Champaign residents, like Debby Auble, who share concerns over the assessment process said some properties are being aggressively overassessed.

“We try to make sure we’re consistent,” said township assessor Brian Christie.

Assessors estimate market value for a particular home as closely as they can using guidelines such as square footage, garage size, number of stories and foundation types.

The condition of the property is also taken into account.

“This is a very subjective thing,” Christie said.

The assessor also uses a “mass appraisal” technique, in which homes are grouped into neighborhoods and assessed based on a mean value of comparable properties around them.

Anywhere between 500 and 1,500 properties are appraised at one time, Christie said.

Auble owns Ward and Associates Realtors, Inc. and she said she has helped more than 200 of the 261 Champaign residents who filed appeals this year.

Auble said that assessments are inconsistent from block to block.

Some inexpensive houses are “grossly overassessed,” she said, while more expensive homes less than a mile away are underassessed.

“There’s only certain times you can do anything about it,” Auble said. “It’s a very complicated process.”

Christie said it is difficult for the assessor’s office to determine what a home is worth when it only has limited information.

“We don’t know what someone’s going to pay for something,” Christie said.

“And we don’t know what’s going on inside a property.”