The typical asking rate per listing is in the $20's per square foot per year. The Tempe region is going through a decline in rates. In the last 3 months, the median rate decreased $4 per sqft per year. That's a 13% decline in rent.
Compared to the rest of the Phoenix Metropolitan Area market, the Tempe region has lower rates, so you should have no trouble finding a great deal in this discounted region.
In the last 90 days, 142 listings have come on the market, so you'll want to check back regularly for new listings. About 7% of the available space in the Tempe are subleases, so you will probably need to sign a longer term lease with the landlord directly. 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 2,190 sqft. Most properties in this region are approximately 2 floors. Most buildings in this market were built in 1987 and are Class B.