Hi
What is the best practices for RMA process in Netsuite?

1)  We have customers who return us items which failed under warranty.
2)  We replace with a similar item from inventory, instead of issuing them a refund.  The replacement has a new serial number
3)  The warranty entitlement of the new serial number starts from the date of sale of the old serial number, not the new serial number
4)  We return the failed item to our supplier for replacement.
5)  Our supplier gives us a replacement with another serial number, with the start date of the replacement starting from the date of the failed serial number