Most listings are in the $50's per square foot per year. The Aventura region is going through a an increase in rates. In the last 3 months, the median rate went up $15 per sqft per year. That's a 33% increase in rent.
Compared to the rest of the Gold Coast market, the Aventura region has higher rates, and you'll need to make a great offer to be in this hot region.
In the last 90 days, 10 listings have come on the market, which means leases might be leasing quickly. You'll want to be prepared to make an offer immediately. About 10% of the office spaces in the Aventura are subleases, so you will probably need to sign a longer term lease with the landlord directly. 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 2,100 sqft. Most properties in this area are close to 9 stories. Most buildings in this area were built in 1988 and are Class A.