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 submarket.
In the last 90 days, 2 listings have been listed, which means spaces most likley are leasing quickly. You'll want to be prepared to make an offer immediately. About 150% of the available leases in the Lemon Grove are subleases, so you might be able to find a shorter term or below market rent. 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 660 sqft. Most buildings in this area are around 2 floors. Most buildings in this region were built in 1985 and are Class Class C.