On average, listings lease in the $10's per square foot per year. The Eureka region is going through a an increase in rates. In the last 3 months, the median rate increased $16 per sqft per year.
In the last 90 days, 8 listings have been listed, which means leases might be going fast. You'll want to be prepared to tour spaces as quick as possible. About 100% of the office spaces in the Eureka 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 770 sqft. Most properties in this market are approximately 2 floors. Most buildings in this region were built in 1948 and are Class B.