Service process

Hi experts,

We have service scenario in crm system.

service order contains item level service product(service item) as well as service material(return material).

we have ecc integration with crm.

Once we create service order in crm. should it replicated to ecc?.Or we can create

service conformation for service product(service) as followup document, and return order for service material and replicate it into ecc for delivery.

please can you explain the best practice when you create service order with service products as well as returnable products.

Thanks

siddu