The typical asking rate per listing is in the $20's per square foot per year. The St. Peters region is seeing a decline in rates. In the last 3 months, the median rate decreased $0 per sqft per year. That's a 2% decline in rent.
In the last 90 days, 28 listings have been posted online, which means new availabilities are probably going fast. You'll want to be prepared to make an offer immediately. About 50% of the available leases in the St. Peters 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 1,310 sqft. Most buildings in this region are around 1 floors. Most buildings in this region were built in 1999 and are Class B.