Most listings are in the $20's per square foot per year. The St. Peters region is going through a decline in rates. In the last 3 months, the median rate fell $2 per sqft per year. That's a 10% decline in rent.
In the last 90 days, 28 listings have been posted online, which means new availabilities most likley are leasing quickly. You'll want to be prepared to make an offer immediately. There aren't many listings below 2,000 square feet posted, so finding a space for a small business might be tough.
Even though the median size is 3,300 sqft, there are still 0 new listings below 2,000 sqft. Most buildings in this area are around 1 stories. Most buildings in this market were built in 1999 and are Class B.