Most listings are in the $20's per square foot per year. The Naples submarket is seeing a decline in rates. In the last 3 months, the median rate decreased $3 per sqft per year. That's a 8% decline in rent.
In the last 90 days, 21 listings have been listed, which means leases most likley are going fast. You'll want to be prepared to make an offer immediately. About 5% of the available leases in the Naples 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 1,950 sqft. Most buildings in this area are approximately 2 floors. Most buildings in this market were built in 1985 and are Class A.