Custer County is in Black Hills & Badlands South Dakota. Of the 66 counties in the Mount Rushmore State, Custer County is 16th in terms of its size (997,800 acres). Recent listings of commercial land and property for sale in South Dakota's Custer County totals almost 1,000 acres and a combined market value of $2 million. The most common type of land for sale by combined acreage in Custer County is residential property. The average price of commercial acreage for sale in Custer County was $577,966. Browse all South Dakota commercial land and property for sale on the Land Network to find your next commercial property or land investment.