Topic: One item with different variants

We are primarily a valve repair company, but sometime we sell new/used/remanufactured valves and sometimes buy defective Cores.  What is the best way to setup our inventory where we can enter the valve number sku example "valve123" and "repair"?
We always have the same variants Repair/New/Used/Reman/Core, but we do not want to add 5 inventory items for each item.
Also our pricing levels are all fix based on the new price and the rest are percentages. the core being the least 5%.
What is the best way to establish best practices?

Re: One item with different variants

you will have to define them separately to distinguish between new and old ones and check the inventory status