The typical asking rate per listing is in the $40's per square foot per year. The Vista submarket is going through a a boost in rates. In the last 3 months, the median rate increased $15 per sqft per year. That's a 53% increase in rent.
Compared to the rest of the San Diego market, the Vista submarket has more expensive rates, and you'll have to negotiate above asking rent to be in this hot region.
In the last 90 days, 41 listings have been listed, so you'll want to check back regularly for new listings. About 2% of the available space in the Vista 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 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 900 sqft. Most buildings in this region are approximately 2 floors. Most buildings in this area were built in 1999 and are Class B.