Home sales prices may be reaching a plateau in Rock County.  After years of steadily climbing prices the Wisconsin Realtors Association reports the median sales price of an existing home in Rock County was less than one-percent higher in October compared to the same month a year ago.  The median sales price in October was more than $202 thousand.  In Green County, sales prices still appear to be on the rise.  The median sales price for an existing Green County home in October saw an increase of 14% over the same month last year.  The WRA reports the median sales price for was $269 thousand.