Most listings are in the $20's per square foot per year. The Portland submarket is seeing a a rise in rates. In the last 3 months, the median rate went up $7 per sqft per year. That's a 33% increase in rent.
In the last 90 days, 44 listings have been listed, so you'll want to check back regularly for new listings. About 89% of the available space in the Portland 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 posted, so finding a space for a small business might be tough.
The standard measurement for office space in this area is around 1,830 sqft. Most buildings in this market are around 3 stories. Most buildings in this area were built in 1900 and are Class B.