On average, listings lease in the $20's per square foot per year. The Lake Magdalene submarket is going through a a boost in rates. In the last 3 months, the median rate went up $0 per sqft per year. That's a 1% rise in rent.
In the last 90 days, 8 listings have been made available, which means new listings most likley are leasing quickly. You'll want to be prepared to make an offer immediately. 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 480 sqft. Most properties in this region are around 1 floors. Most buildings in this area were built in 0 and are Class B.