AIKEN --- That 15 percent cap on property taxes voters approved is costing Aiken County more than the potential loss of revenue.

It also forced significant changes in the software the county uses to calculate property owners' bills. Those programming alterations came with a hefty price tag: $60,990.

That's how much the county paid CSRA Computer Service of North Augusta, which designed and supports the software programs Aiken County uses to calculate property taxes and generate assessment notices.

"If the Legislature had not made any changes, there wouldn't be any additional charges," said Johnny Walton, the director of the county's information technology department.

"I thought it was a little high," County Administrator Clay Killian said, "but we didn't have a choice."

It wasn't just the cap that prompted the pricey changes. In addition to keeping taxable property values from skyrocketing between assessments, the software also had to account for changes in the school tax credit law.

There were other costs, but the 15 percent cap accounts for the largest portion of the bill, Mr. Walton said.

The invoice sent to county council members shows that changing the software to account for the cap cost $30,000 alone.

The county's treasurer, auditor and delinquent tax collector's office use the software to send out about 100,000 real property tax bills and about 54,000 assessment notices, Mr. Killian said.

Mr. Walton said CSRA Computer Service workers also attended meetings with state and county officials to hammer out details about the cap.

Many counties have delayed reassessments, Mr. Walton said, because of the uncertainty and the complex calculations.

CSRA Computer Service is under contract with the county and is paid $40,000 a year to maintain and support its software.

Mr. Walton said that minor changes are included within the contract.

"Usually those are a few hundred dollars, if anything," he said. "They do that as part of the contract."