Escambia County Property Appraiser Chris Jones says his office is working to collect back property taxes and a Louisiana-based company has been hired to assist. The company will use high-tech tools to track down invalid homestead exemptions and collect what is rightfully due, plus penalties and interest. Unpaid taxes for an invalid homestead exemption can be collected for up to 10 years ago, plus a penalty of 50% of the unpaid taxes for each year, plus 15% annual interest. Currently, about 40 percent of taxpayers identified with an invalid exemption come in and pay, while 60 percent will have a lien filed against the property.