On average, listings lease in the $20's per square foot per year. The Castle Hills region is going through a a boost in rates. In the last 3 months, the median rate rose $30 per sqft per year.
Compared to the rest of the Greater Austin market, the Castle Hills submarket has greater rates, and you'll need to make a great offer to be in this hot submarket.
In the last 90 days, 19 listings have been posted online, which means listings most likley are going fast. You'll want to be prepared to tour spaces as quick as possible. About 79% of the available leases in the Castle Hills are subleases, so you might be able to snag a great spot on a short term. There aren't many listings below 2,000 square feet on the market, 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 area are close to 4 floors. Most buildings in this market were built in 1982 and are Class B.