Custer County is in Black Hills & Badlands South Dakota. Of the 66 counties in the Coyote State, 1,559-square-mile Custer County ranks 16th by size. Custer County, South Dakota, has about 1,000 acres of farms for sale based on recent Land Network data. The combined market value of land for sale here was around $1 million. The average price of farms for sale in Custer County was $350,000. Browse all South Dakota farms for sale on the Land Network to find the farm, cattle operation, hobby farm or other farm property that's right for your future commercial or lifestyle needs.