Sub-Contracting Scenario

Hi Gurus,

My client is one of the leading laptop manufacturer.

We have a below scenario. Kindly help to map it in SAP.

Client send a laptop to subcontracting vendor to resemble, subcontracting vendor resembles laptop and need to return all the spares to client.

Here component is laptop(child material) and spares are the parent materials.

How to create PO for this? If we create PO with all components line by line, how we have to maintain BOM for each line means it makes no sense.

I have gone through dismantle process. Answers were not satisfied.