87 homes are presently on the market in Mercer County. That number is from the Illinois Association of REALTORS. The organization shows there were eight closed sales last month with a median sales price of almost $131,000. Year to date, 101 homes have sold in Mercer County in 2013 with an average price of $89,000. That compares to 97 last year at this time with an average price of $84,000. So far this year, a home sits on the market 99 days on average before a closed sale in Mercer County.