On average, listings lease in the $20's per square foot per year. The Nassau County region is going through a a rise in rates. In the last 3 months, the median rate increased $24 per sqft per year.
In the last 90 days, 14 listings have been listed, which means new listings might be going fast. You'll want to be prepared to make an offer immediately. About 7% of the listings in the Nassau County 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 posted, so finding a space for a small business might be tough.
The standard measurement for office space in this area is around 1,810 sqft. Most properties in this region are approximately 2 stories. Most buildings in this region were built in 2000 and are Class B.