Most listings are in the $10's per square foot per year. The Westfield region is going through a an increase in rates. In the last 3 months, the median rate rose $17 per sqft per year.
In the last 90 days, 3 listings have been listed, which means leases most likley are going fast. You'll want to be prepared to make an offer immediately. There aren't many listings below 2,000 square feet on the market, so finding a space for a small business might be tough.
The standard measurement for office space in this area is around 2,450 sqft. Most buildings in this area are approximately 1 stories. Most buildings in this market were built in 1994 and are Class A.