Most listings are in the $10's per square foot per year. The Harrisburg 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% decline in rent.
In the last 90 days, 20 listings have been posted online, which means new listings most likley are going fast. You'll want to be prepared to make an offer immediately. About 10% of the office spaces in the Harrisburg are subleases, so you will probably have to focus your search on direct office leases. 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 buildings in this region are around 3 floors. Most buildings in this region were built in 1940 and are Class B.