Most listings are in the $20's per square foot per year. The Johnson County region is experiencing a an increase in rates. In the last 3 months, the median rate went up $3 per sqft per year. That's a 14% increase in rent.
In the last 90 days, 12 listings have been made available, which means leases most likley are leasing quickly. You'll want to be prepared to make an offer immediately. About 8% of the available leases in the Johnson County are subleases, so you will probably need to sign a longer term lease with the landlord directly. There aren't many listings below 2,000 square feet on the market, so finding a space for a small business might be tough.
Even though the median size is 3,000 sqft, there are still 0 new listings below 2,000 sqft. Most properties in this region are around 1 floors. Most buildings in this market were built in 1966 and are Class B.