The typical asking rate per listing is in the $10's per square foot per year. The Post Falls submarket is going through a decline in rates. In the last 3 months, the median rate decreased $2 per sqft per year. That's a 10% decline in rent.
In the last 90 days, 13 listings have been made available, which means listings most likley are leasing quickly. You'll want to be prepared to make an offer immediately. About 8% of the available leases in the Post Falls are subleases, so you will probably have to focus your search on direct office leases. 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 2,030 sqft. Most buildings in this market are around 1 floors. Most buildings in this region were built in 1979 and are Class B.