On average, listings lease in the $20's per square foot per year. The St. Petersburg submarket is going through a a rise in rates. In the last 3 months, the median rate rose $1 per sqft per year. That's a 3% increase in rent.
In the last 90 days, 107 listings have been posted online, so you'll want to check back regularly for new listings. About 3% of the available space in the St. Petersburg are subleases, so you will probably have to consider a longer term 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.
Even though the median size is 3,380 sqft, there are still 0 leases below 2,000 sqft. Most buildings in this region are close to 2 stories. Most buildings in this area were built in 1950 and are Class B.