New to SAGE Contractor 100. Trying to get my head around the structure. 

Account Code

Sub-account code

Cost code

Cost type

For example I have an expense for renting a forklift for setting up on a new construction site on a bridge. I also work on dams. I rent lots of different pieces of heavy equipment. I use a forklift for mobilizing (set-up a job site and I use it during deconstruction. I also use it for re-constructing. So, with all that said. This is how I believe I want it said up.

1) I think I want departments for setting up the job: So in this case I have a new job that I want to code to the bridge department vs. the dam department. This might be helpful with later analysis trying to understand if bridge or more profitable than dams. 

2) I would code this to rental major GL account and this particular GL account would also have a sub account called forklifts because I also rent a lot of generators and I want to have a different sub-account.

3) since the forklift is being used for mobilization vs deconstruction or construction I want to code this to cost code mobilization

4) finally, I still have an option for cost type. I can't get my head around why I would use this code. Sure, it might go the rental as a cost type, but I have that information identified in the GL.

5) So my real question is - What is the purpose of cost type?