On average, listings lease in the $20's per square foot per year. The St. Petersburg region is experiencing a a rise in rates. In the last 3 months, the median rate went up $1 per sqft per year. That's a 5% increase in rent.
In the last 90 days, 90 listings have been listed, so you'll want to check back regularly for new listings. About 3% of the listings in the St. Petersburg are subleases, so you will probably need to consider the implications of signing a direct lease with the building. There aren't many listings below 2,000 square feet available, so finding a space for a small business might be tough.
The standard measurement for office space in this area is around 2,060 sqft. Most properties in this market are approximately 2 stories. Most buildings in this area were built in 1952 and are Class B.