Most listings are in the $20's per square foot per year. The Colorado region is going through a a boost in rates. In the last 3 months, the median rate increased $0 per sqft per year. That's a 2% rise in rent.
In the last 90 days, 1677 listings have been listed, so you'll want to check back regularly for new listings. About 4% of the available leases in the Colorado are subleases, so you will probably have to consider a longer term lease. There aren't many listings below 2,000 square feet posted, so finding a space for a small business might be tough.
The standard measurement for office space in this area is around 2,040 sqft. Most buildings in this region are around 2 stories. Most buildings in this market were built in 1980 and are Class B.