Inventory Start Over

Our inventory right now is a mess, duplicate items with different part numbers, negative quantities, a naming convention that has no rules, etc. and I've been tasked with rebuilding the system. This mainly means creating a new universal naming convention, taking a fresh inventory, and plugging in the values (basically creating a whole new inventory)

Our plan is to implement this at the beginning of the fiscal year, so this gives us 7 months to set it up. I understand that all the parts are linked to invoices and estimates, so deleting everything is not the answer (and also impossible). Our plan is to eventually make everything inactive once all the old invoices are paid, and any new invoices or estimates will use the new naming convention. 

I am going to create new item names, take the inventory, and use those items on all new estimates beginning Jan 1 as if it's a whole new business, completely ignoring the old names. Once we are using the new items, I will manually change the old items quantity to 0 and once all the invoices are paid and settled make everything inactive. In theory this will give us a fresh inventory moving forward.

Can anyone advise me on what can go wrong doing this process, or if there's a better way to do it (other than starting a whole new QB account from scratch). I know this is going to be a lot of work on my end, I'm considering using a barcode scanner to help, so any thoughts on that would be beneficial as well.

Thanks for any advice and help,

Jon