The typical asking rate per listing is in the $20's per square foot per year. The San Luis Obispo region is going through a a boost in rates. In the last 3 months, the median rate went up $2 per sqft per year. That's a 6% rise in rent.
In the last 90 days, 20 listings have been posted online, which means new listings most likley are going fast. You'll want to be prepared to make an offer immediately. About 10% of the office spaces in the San Luis Obispo are subleases, so you will probably need to consider the implications of signing a direct lease with the building. There aren't many listings below 2,000 square feet available, so finding a space for a small business might be tough.
The standard measurement for office space in this area is around 1,680 sqft. Most buildings in this market are approximately 2 floors. Most buildings in this region were built in 2009 and are Class A.