The typical asking rate per listing is in the $20's per square foot per year. The San Luis Obispo submarket is seeing a an increase in rates. In the last 3 months, the median rate rose $2 per sqft per year. That's a 6% rise in rent.
In the last 90 days, 25 listings have been made available, which means leases most likley are going fast. You'll want to be prepared to make an offer immediately. About 16% of the office spaces in the San Luis Obispo 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 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 2,220 sqft. Most buildings in this region are close to 2 stories. Most buildings in this market were built in 2000 and are Class A.