The typical asking rate per listing is in the $20's per square foot per year. The Bexar County region is going through a a rise in rates. In the last 3 months, the median rate rose $1 per sqft per year. That's a 5% increase in rent.
Compared to the rest of the Greater Austin market, the Bexar County region has smaller rates, so you should have no trouble finding a great deal in this discounted region.
In the last 90 days, 280 listings have been posted online, so you'll want to check back regularly for new listings. About 1% of the available space in the Bexar County 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.
Even though the median size is 2,510 sqft, there are still 0 leases below 2,000 sqft. Most properties in this area are close to 2 floors. Most buildings in this market were built in 1985 and are Class A.