Most listings are in the $20's per square foot per year. The Castle Hills region is going through 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 Greater Austin market, the Castle Hills region has less expensive rates, so you should have no trouble finding a great deal in this depreciated submarket.
In the last 90 days, 19 listings have been listed, which means office spaces 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 available, so finding a space for a small business might be tough.
Even though the median size is 4,230 sqft, there are still 0 listings below 2,000 sqft. Most properties in this region are close to 4 floors. Most buildings in this area were built in 1982 and are Class B.