Building Designer:- Design is the first communication medium in between designer and the customer. This is basically a 2d form of art. To understand the orientation of a building.
3d Designer:- This will give you details projection of your House. How it will look after Compleat the project. It will help you if someone who constructs something for commercial uses.
Estimator:- You need proper estimation. To full feel all requirements and cost for the project.