On average, listings lease in the $10's per square foot per year. The Garland region is seeing a an increase in rates. In the last 3 months, the median rate rose $3 per sqft per year. That's a 15% increase in rent.
Compared to the rest of the DFW Metroplex market, the Garland region has less expensive rates, so you should have no trouble finding a great deal in this discounted submarket.
In the last 90 days, 19 listings have been posted online, which means new listings most likley are 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 1,750 sqft. Most buildings in this region are close to 1 stories. Most buildings in this area were built in 1983 and are Class B.