The typical asking rate per listing is in the $30's per square foot per year. The Vacaville region is seeing a a rise in rates. In the last 3 months, the median rate rose $5 per sqft per year. That's a 17% rise in rent.
Compared to the rest of the Bay Area market, the Vacaville region has less expensive rates, so you should have no trouble finding a great deal in this discounted region.
In the last 90 days, 1 listings have been posted online, which means office spaces most likley are going fast. You'll want to be prepared to tour spaces as quick as possible. About 100% of the office spaces in the Vacaville 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 1,080 sqft. Most buildings in this region are around 1 stories. Most buildings in this region were built in 1990 and are Class B.