On average, listings lease in the $0's per square foot per year. The Gunbarrel region is seeing a decline in rates. In the last 3 months, the median rate fell $19 per sqft per year. That's a 100% decline in rent.
In the last 90 days, 1 listings have been made available, which means listings are probably going fast. You'll want to be prepared to make an offer immediately. 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 sqft.