Most listings are in the $10's per square foot per year. The Okemos submarket is experiencing a decrease in rates. In the last 3 months, the median rate decreased $1 per sqft per year. That's a 7% decrease in rent.
In the last 90 days, 40 listings have been listed, which means new listings most likley are going fast. You'll want to be prepared to make an offer immediately. About 3% of the available space in the Okemos 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 available, so finding a space for a small business might be tough.
The standard measurement for office space in this area is around 1,200 sqft. Most buildings in this market are around 1 floors. Most buildings in this region were built in 1985 and are Class A.