The typical asking rate per listing is in the $20's per square foot per year. The Castle Rock submarket is going through a decline in rates. In the last 3 months, the median rate fell $5 per sqft per year. That's a 20% decrease in rent.
Compared to the rest of the Denver Metro market, the Castle Rock submarket has less expensive rates, so you should have no trouble finding a great deal in this discounted submarket.
In the last 90 days, 11 listings have been listed, which means office spaces most likley are going fast. You'll want to be prepared to tour spaces as quick as possible. About 9% of the office spaces in the Castle Rock are subleases, so you will probably have to focus your search on direct office leases. 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 1,820 sqft. Most properties in this area are close to 2 stories. Most buildings in this area were built in 1993 and are Class B.