The typical asking rate per listing is in the $10's per square foot per year. The Rapid City region is experiencing a a rise in rates. In the last 3 months, the median rate increased $16 per sqft per year.
In the last 90 days, 56 listings have been made available, so you'll want to check back regularly for new listings. About 61% of the available leases in the Rapid City are subleases, so you might be able to find a shorter term or below market rent. There aren't many listings below 2,000 square feet available, so finding a space for a small business might be tough.
The standard measurement for office space in this area is around 1,000 sqft. Most buildings in this area are close to 2 stories. Most buildings in this region were built in 1986 and are Class B.