Most listings are in the $10's per square foot per year. The Brent region is seeing a a rise in rates. In the last 3 months, the median rate increased $0 per sqft per year. That's a 2% increase in rent.
In the last 90 days, 11 listings have been posted online, which means new availabilities are probably going fast. You'll want to be prepared to tour spaces as quick as possible. About 145% of the available leases in the Brent 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 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 1,790 sqft. Most properties in this market are approximately 1 stories. Most buildings in this market were built in 1979 and are Class B.