LOD 400 and LOD 500 are different for sure, LOD 400 is like I know what the model and size and every detail about what I want to purchase for the project and LOD 500 is more like for existing and inventory listing. Work loads is a strange way to ask this question. If you want to know how may people or man hours to model to that level, well its hard to say, contact me and I can work through the details to figure out how long it might take. Go here is will describe the LOD for elements. bimforum.org/lod/
