On average, listings lease in the $10's per square foot per year. The Amarillo region is going through a a boost in rates. In the last 3 months, the median rate rose $1 per sqft per year. That's a 4% rise in rent.
In the last 90 days, 107 listings have come on the market, so you'll want to check back regularly for new listings. 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 1,210 sqft. Most properties in this area are approximately 1 stories. Most buildings in this region were built in 1970 and are Class A.