Most listings are in the $10's per square foot per year. The Lemon Grove submarket is seeing a an increase in rates. In the last 3 months, the median rate went up $14 per sqft per year. That's a Inf% rise in rent.
Compared to the rest of the San Diego market, the Lemon Grove submarket has lower rates, so you should have no trouble finding a great deal in this undervalued region.
In the last 90 days, 5 listings have been made available, which means spaces most likley are going fast. 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 780 sqft. Most buildings in this area are around 2 floors. Most buildings in this area were built in 1985 and are Class Class C.