On average, listings lease in the $40's per square foot per year. The Yonkers submarket is going through a a boost in rates. In the last 3 months, the median rate increased $50 per sqft per year.
In the last 90 days, 7 listings have been listed, which means new availabilities most likley are going fast. You'll want to be prepared to tour spaces as quick as possible. About 129% of the listings in the Yonkers are subleases, so you might be able to sign a shorter term by taking over a previous lease. 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 1,690 sqft. Most buildings in this region are around 2 stories. Most buildings in this area were built in 1987 and are Class A.