On average, listings lease in the $10's per square foot per year. The Porterville region is going through a decline in rates. In the last 3 months, the median rate fell $2 per sqft per year. That's a 9% decline in rent.
In the last 90 days, 2 listings have been listed, which means spaces are probably leasing quickly. You'll want to be prepared to make an offer immediately. 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 1,460 sqft. Most buildings in this region are close to 1 stories. Most buildings in this market were built in 2001 and are Class B.