Most listings are in the $20's per square foot per year. The King City submarket is going through a an increase in rates. In the last 3 months, the median rate went up $24 per sqft per year.
Compared to the rest of the Greater Portland market, the King City region has lower rates, so you should have no trouble finding a great deal in this undervalued region.
In the last 90 days, 0 listings have been posted online, which means new listings are probably leasing quickly. You'll want to be prepared to make an offer immediately. About NaN% of the office spaces in the King City 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 posted, so finding a space for a small business might be tough.
The standard measurement for office space in this area is around 1,360 sqft. Most buildings in this area were built in 1978 and are Class B.