On average, listings lease in the $0's per square foot per year. The Gunbarrel region is going through a decline in rates. In the last 3 months, the median rate decreased $19 per sqft per year. That's a 100% decline in rent.
In the last 90 days, 1 listings have come on the market, which means listings 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 available, so finding a space for a small business might be tough.
The standard measurement for office space in this area is around sqft.