Inventory set up

1: Is there is a way to set up inventory item with my own Item number and the vendor’s item number so when I prepare the purchase PO, it shows the vendor/supplier’s item number; and when I prepare my sales invoice it shows my item’s number? That way the inventory flows in and flows out the same item number in my system?

2: We have many old pending Purchase PO left inside the system as they did not go through inventory in-inventory out cycle. How can I clear these PO fast and correctly?

3: I want to be able to generate sales report by sales rep and by region (province/state), is it possible with Sage 50?

4: I want my customer/vendor window to display the history of their transactions/record without going through the report or find function, is it possible?