On average, listings lease in the $10's per square foot per year. The Lebanon submarket is experiencing a a boost in rates. In the last 3 months, the median rate went up $17 per sqft per year.
In the last 90 days, 5 listings have been made available, which means office spaces are probably going fast. You'll want to be prepared to make an offer immediately. About 20% of the office spaces in the Lebanon are subleases, so you might be able to sign a shorter term by taking over a previous lease. 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 2,200 sqft. Most buildings in this region were built in 1989 and are Class A.