On average, listings lease in the $10's per square foot per year. The Milwaukie submarket is seeing a decrease in rates. In the last 3 months, the median rate decreased $7 per sqft per year. That's a 32% decline in rent.
Compared to the rest of the Greater Portland market, the Milwaukie submarket has lower rates, so you should have no trouble finding a great deal in this discounted region.
In the last 90 days, 2 listings have been made available, which means leases most likley are going fast. You'll want to be prepared to make an offer immediately. 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 690 sqft. Most properties in this area are close to 2 stories. Most buildings in this market were built in 1988 and are Class B.