Yes - We do 6 different lengths and 3 different widths. 
The largest transportable home we build is 12.5m (long) X 4.4m (wide). Most of our units are either 3.0m or 3.6m in width and vary in size by length. We generally refer to them by their length. We have a range of standard lengths and don't do customised sizes. Your options are 6.2m, 7.4m, 8.4m, 9.4m, 10.4m, and 12.5m long, and 3m, 3.6m, or 4.4m wide.