Inventory Item

I am using SAP B1. If I have single item in different divisions of my company, and I want to open them with different item codes I need to know about two things:

1) How can I transfer between two divisions? I mean is there a way to transfer item from One Item Code to another Item Code?

2) How can I see the total inventory of that item in my company? I couldn't find any Parent Item concept in this case?

I have another question that is if I do not want to use virtual locations within a single location (Suppose I have 2 divisions A1 and B1 and in my location L I have kept two virtual ones LA and LB for both divisions). Can I use the concept of BIN rather than using virtual warehouses in SAP B1? Someone said it would affect my MRP later on....