Most listings are in the $20's per square foot per year. The Benbrook submarket is going through a decrease in rates. In the last 3 months, the median rate fell $3 per sqft per year. That's a 13% decrease in rent.
Compared to the rest of the DFW Metroplex market, the Benbrook region has smaller rates, so you should have no trouble finding a great deal in this depreciated submarket.
In the last 90 days, 10 listings have been listed, which means new listings are probably leasing quickly. You'll want to be prepared to make an offer immediately. 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 1,550 sqft. Most properties in this area are around 2 floors. Most buildings in this market were built in 1986 and are Class C.