On average, listings lease in the $10's per square foot per year. The Winchester submarket is going through a a rise in rates. In the last 3 months, the median rate rose $20 per sqft per year.
In the last 90 days, 12 listings have been listed, which means spaces are probably going fast. You'll want to be prepared to make an offer immediately. There aren't many listings below 2,000 square feet posted, so finding a space for a small business might be tough.
The standard measurement for office space in this area is around 1,800 sqft. Most buildings in this market are close to 2 stories. Most buildings in this market were built in 1997 and are Class A.