Most listings are in the $0's per square foot per year. The Berwyn region is experiencing a decline in rates. In the last 3 months, the median rate fell $20 per sqft per year. That's a 100% decline in rent.
In the last 90 days, 4 listings have been posted online, which means office spaces are probably leasing quickly. You'll want to be prepared to make an offer immediately. There aren't many listings below 2,000 square feet available, so finding a space for a small business might be tough.
The standard measurement for office space in this area is around sqft. Most properties in this market are approximately 2 floors. Most buildings in this area were built in 1911 and are Class C.