On average, listings lease in the $20's per square foot per year. The Hayward region is going through a a rise in rates. In the last 3 months, the median rate went up $6 per sqft per year. That's a 30% increase in rent.
Compared to the rest of the East Bay market, the Hayward region has lower rates, so you should have no trouble finding a great deal in this undervalued submarket.
In the last 90 days, 22 listings have been posted online, which means office spaces are probably leasing quickly. You'll want to be prepared to make an offer immediately. About 9% of the available space in the Hayward 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 4,600 sqft, there are still 0 spaces below 2,000 sqft. Most properties in this area are close to 1 floors. Most buildings in this region were built in 1979 and are Class A.