On average, listings lease in the $10's per square foot per year. The Mandan region is experiencing a decrease in rates. In the last 3 months, the median rate decreased $13 per sqft per year. That's a 42% decrease in rent.
In the last 90 days, 1 listings have been posted online, which means new availabilities are probably going fast. You'll want to be prepared to tour spaces as quick as possible. About 1,500% of the available leases in the Mandan are subleases, so you might be able to sign a shorter term by taking over a previous lease. There aren't many listings below 2,000 square feet on the market, so finding a space for a small business might be tough.
The standard measurement for office space in this area is around 2,200 sqft. Most buildings in this market were built in 1984 and are Class A.