Most listings are in the $20's per square foot per year. The San Luis Obispo submarket is seeing a a rise in rates. In the last 3 months, the median rate rose $4 per sqft per year. That's a 17% increase in rent.
In the last 90 days, 51 listings have come on the market, so you'll want to check back regularly for new listings. About 2% of the listings in the San Luis Obispo are subleases, so you will probably need to sign a longer term lease with the landlord directly. 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 1,250 sqft. Most properties in this area are approximately 2 stories. Most buildings in this area were built in 2002 and are Class A.