On average, listings lease in the $20's per square foot per year. The Concord submarket is seeing a decline in rates. In the last 3 months, the median rate decreased $10 per sqft per year. That's a 24% decline in rent.
Compared to the rest of the East Bay market, the Concord region has less expensive rates, so you should have no trouble finding a great deal in this depreciated submarket.
In the last 90 days, 34 listings have been listed, which means new availabilities most likley are leasing quickly. You'll want to be prepared to make an offer immediately. About 6% of the listings in the Concord 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 available, so finding a space for a small business might be tough.
Even though the median size is 16,000 sqft, there are still 0 office spaces below 2,000 sqft. Most properties in this area are approximately 2 stories. Most buildings in this market were built in 1982 and are Class A.