Most listings are in the $20's per square foot per year. The San Luis Obispo region is going through a a rise in rates. In the last 3 months, the median rate went up $28 per sqft per year.
In the last 90 days, 20 listings have been listed, which means leases most likley are leasing quickly. You'll want to be prepared to tour spaces as quick as possible. About 65% of the available space in the San Luis Obispo are subleases, so you might be able to snag a great spot on a short term. There aren't many listings below 2,000 square feet on the market, so finding a space for a small business might be tough.
Even though the median size is 2,600 sqft, there are still 0 spaces below 2,000 sqft. Most properties in this area are approximately 2 floors. Most buildings in this region were built in 2009 and are Class A.