On average, listings lease in the $20's per square foot per year. The Baytown region is experiencing a a boost in rates. In the last 3 months, the median rate increased $22 per sqft per year.
Compared to the rest of the Houston Metro market, the Baytown submarket has lower rates, so you should have no trouble finding a great deal in this depreciated region.
In the last 90 days, 7 listings have been made available, which means listings most likley are going fast. You'll want to be prepared to make an offer immediately. 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 1,700 sqft. Most properties in this region are around 1 floors. Most buildings in this market were built in 1984 and are Class B.