The typical asking rate per listing is in the $10's per square foot per year. The Montgomery submarket is going through a decrease in rates. In the last 3 months, the median rate fell $1 per sqft per year. That's a 7% decrease in rent.
In the last 90 days, 65 listings have been made available, so you'll want to check back regularly for new listings. About 2% of the listings in the Montgomery 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 posted, so finding a space for a small business might be tough.
The standard measurement for office space in this area is around 1,860 sqft. Most properties in this market are around 2 floors. Most buildings in this region were built in 1977 and are Class B.