The typical asking rate per listing is in the $20's per square foot per year. The Grapevine region is experiencing a decline in rates. In the last 3 months, the median rate decreased $3 per sqft per year. That's a 9% decline in rent.
Compared to the rest of the DFW Metroplex market, the Grapevine submarket has more expensive rates, and you'll have to negotiate above asking rent to be in this hot submarket.
In the last 90 days, 19 listings have been posted online, which means leases most likley are leasing quickly. You'll want to be prepared to make an offer immediately. About 5% of the listings in the Grapevine 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 on the market, so finding a space for a small business might be tough.
The standard measurement for office space in this area is around 2,050 sqft. Most buildings in this area are close to 1 stories. Most buildings in this area were built in 2005 and are Class B.