On average, listings lease in the $20's per square foot per year. The Tucson region is going through a a rise in rates. In the last 3 months, the median rate went up $4 per sqft per year. That's a 24% rise in rent.
Compared to the rest of the Tucson Metropolitan Area market, the Tucson region has less expensive rates, so you should have no trouble finding a great deal in this depreciated region.
In the last 90 days, 111 listings have come on the market, so you'll want to check back regularly for new listings. About 5% of the available leases in the Tucson are subleases, so you will probably have to consider a longer term lease. There aren't many listings below 2,000 square feet posted, so finding a space for a small business might be tough.
The standard measurement for office space in this area is around 2,200 sqft. Most buildings in this region are approximately 2 floors. Most buildings in this area were built in 1982 and are Class B.