In the last 90 days, 2 listings have been posted online, which means leases most likley are leasing quickly. You'll want to be prepared to make an offer immediately. About 200% of the listings in the Niagara Falls are subleases, so you might be able to snag a great spot on a short term. 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 sqft. Most buildings in this area are around 2 floors. Most buildings in this region were built in 1960 and are Class C.