The typical asking rate per listing is in the $20's per square foot per year. The Spokane submarket is going through a an increase in rates. In the last 3 months, the median rate went up $21 per sqft per year.
In the last 90 days, 114 listings have been listed, so you'll want to check back regularly for new listings. About 163% of the listings in the Spokane 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 on the market, so finding a space for a small business might be tough.
The standard measurement for office space in this area is around 1,560 sqft. Most properties in this region are around 2 stories. Most buildings in this region were built in 1966 and are Class B.