On average, listings lease in the $20's per square foot per year. The Irving submarket is seeing a a boost in rates. In the last 3 months, the median rate went up $0 per sqft per year. That's a 0% increase in rent.
Compared to the rest of the DFW Metroplex market, the Irving submarket has greater rates, and you'll need to make a great offer to be in this hot region.
In the last 90 days, 338 listings have been posted online, so you'll want to check back regularly for new listings. About 4% of the listings in the Irving are subleases, so you will probably need to sign a longer term lease with the landlord directly. 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 1,300 sqft. Most buildings in this market are close to 2 floors. Most buildings in this area were built in 1985 and are Class B.