The typical asking rate per listing is in the $20's per square foot per year. The Gilbert submarket is going through a a boost in rates. In the last 3 months, the median rate went up $1 per sqft per year. That's a 6% rise in rent.
Compared to the rest of the Phoenix Metropolitan Area market, the Gilbert submarket has lower rates, so you should have no trouble finding a great deal in this depreciated region.
In the last 90 days, 96 listings have been posted online, so you'll want to check back regularly for new listings. About 1% of the office spaces in the Gilbert 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.
The standard measurement for office space in this area is around 2,100 sqft. Most properties in this market are approximately 1 stories. Most buildings in this area were built in 2006 and are Class B.