Most listings are in the $20's per square foot per year. The Riverfront region is going through a a boost in rates. In the last 3 months, the median rate went up $23 per sqft per year.
In the last 90 days, 4 listings have been posted online, which means leases most likley are going fast. You'll want to be prepared to tour spaces as quick as possible. There aren't many listings below 2,000 square feet posted, so finding a space for a small business might be tough.
The standard measurement for office space in this area is around 1,470 sqft. Most buildings in this area were built in 1900 and are Class A.
Not much of the real estate is used for commercial space, so it might be hard to find office space. Waste services is the dominant industry in this market. Most of the residents of Riverfront work from home. Commuting between 20 and 25 minutes a day is the norm for those who opt to reside in this part of town.