The typical asking rate per listing is in the $20's per square foot per year. The West Slope region is going through a an increase in rates. In the last 3 months, the median rate increased $22 per sqft per year.
Compared to the rest of the Greater Portland market, the West Slope submarket has lower rates, so you should have no trouble finding a great deal in this undervalued submarket.
In the last 90 days, 1 listings have been posted online, which means office spaces most likley are leasing quickly. You'll want to be prepared to tour spaces as quick as possible. About 100% of the available leases in the West Slope are subleases, so you might be able to find a shorter term or below market rent. 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 960 sqft. Most buildings in this area are close to 2 floors. Most buildings in this area were built in 2005 and are Class B.