On average, listings lease in the $10's per square foot per year. The Monroe region is going through a an increase in rates. In the last 3 months, the median rate rose $19 per sqft per year.
Compared to the rest of the Seattle Metropolitan Area market, the Monroe region has lower rates, so you should have no trouble finding a great deal in this depreciated region.
In the last 90 days, 3 listings have been made available, which means new availabilities are probably going fast. You'll want to be prepared to tour spaces as quick as possible. About 400% of the available space in the Monroe 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 posted, so finding a space for a small business might be tough.
Even though the median size is 31,150 sqft, there are still 0 listings below 2,000 sqft. Most properties in this area are around 2 floors. Most buildings in this region were built in 1995 and are Class C.