On average, listings lease in the $20's per square foot per year. The Wheaton submarket is going through a an increase in rates. In the last 3 months, the median rate increased $0 per sqft per year. That's a 1% rise in rent.
Compared to the rest of the Chicagoland market, the Wheaton region has higher rates, and you'll need to make a great offer to be in this hot submarket.
In the last 90 days, 126 listings have come on the market, so you'll want to check back regularly for new listings. About 2% of the office spaces in the Wheaton 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 410 sqft. Most properties in this region are around 2 floors. Most buildings in this market were built in 1988 and are Class B.