Most listings are in the $10's per square foot per year. The Lexington region is going through a a rise in rates. In the last 3 months, the median rate increased $16 per sqft per year.
In the last 90 days, 2 listings have been made available, which means new availabilities most likley are going fast. You'll want to be prepared to make an offer immediately. About 400% of the listings in the Lexington are subleases, so you might be able to snag a great spot on a short term. 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 1,600 sqft. Most properties in this market are close to 1 floors. Most buildings in this area were built in 2000 and are Class B.