On average, listings lease in the $20's per square foot per year. The Boulder County region is going through a decrease in rates. In the last 3 months, the median rate fell $4 per sqft per year. That's a 15% decline in rent.
In the last 90 days, 160 listings have been posted online, so you'll want to check back regularly for new listings. About 10% of the listings in the Boulder County are subleases, so you will probably need to sign a longer term lease with the landlord directly. 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 2,320 sqft. Most properties in this area are close to 2 floors. Most buildings in this region were built in 1991 and are Class A.