The typical asking rate per listing is in the $10's per square foot per year. The Martinsburg submarket is seeing a an increase in rates. In the last 3 months, the median rate rose $20 per sqft per year. That's a Inf% increase in rent.
In the last 90 days, 3 listings have been listed, which means spaces are probably leasing quickly. You'll want to be prepared to make an offer immediately. 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 1,000 sqft. Most buildings in this region are approximately 2 stories. Most buildings in this market were built in 1989 and are Class C.