On average, listings lease in the $10's per square foot per year. The Old Irving Park region is going through a an increase in rates. In the last 3 months, the median rate went up $1 per sqft per year. That's a 8% rise in rent.
In the last 90 days, 14 listings have been listed, which means leases most likley are leasing quickly. You'll want to be prepared to make an offer immediately. 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 1,190 sqft. Most buildings in this market are approximately 2 floors. Most buildings in this area were built in 1972 and are Class B.
Not much of the real estate is used for commercial space, so it might be hard to find office space. Waste services is the dominant industry in this area. Most of the residents of Old Irving Park work from home. Commuting around an hour and a half a day is the norm for those who opt to reside in this part of town.