Ideally the flow would go like this. 

PO Created, Approved, Processed and when receiving on the PO, I would need to enter the serial number for each of the QTY on the PO. 

I could then run a report and based on the SKU, I could see a list of what I had on hand and what the serial numbers were.  

When processing an Sales ORder, I would need to enter the Serial number for each of the QTY being put on the SO.  (Or it could be at a later point in the workflow for a SO.  

I would then want to be able to run a report based on on my sales and be able to see what the S/N went out on each order.  I would also like to be able to index by the S/N and be able to search for a S/N and see who it went to and when.  

How possible is this with ZOHO CRM and how could it be done?