Most listings are in the $20's per square foot per year. The Renton submarket is going through a decrease in rates. In the last 3 months, the median rate fell $2 per sqft per year. That's a 8% decrease in rent.
Compared to the rest of the Seattle Metropolitan Area market, the Renton submarket has lower rates, so you should have no trouble finding a great deal in this discounted region.
In the last 90 days, 7 listings have been listed, which means new availabilities might be going fast. You'll want to be prepared to make an offer immediately. 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 1,050 sqft. Most buildings in this region are close to 2 stories. Most buildings in this area were built in 1983 and are Class A.