On average, listings lease in the $20's per square foot per year. The Castle Hills region is going through a an increase in rates. In the last 3 months, the median rate rose $13 per sqft per year. That's a 73% increase in rent.
Compared to the rest of the Greater Austin market, the Castle Hills submarket has lower rates, so you should have no trouble finding a great deal in this discounted submarket.
In the last 90 days, 19 listings have been listed, which means new availabilities are probably going fast. You'll want to be prepared to tour spaces as quick as possible. About 42% of the listings in the Castle Hills are subleases, so you might be able to sign a shorter term by taking over a previous lease. 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 3,810 sqft, there are still 0 office spaces below 2,000 sqft. Most buildings in this region are around 4 stories. Most buildings in this region were built in 1982 and are Class B.