Many businesses purchase product from multiple vendors all having different part numbers and costs. One solution is to create a separate item for each vendor however you will quickly realize this is not a workable solution because you will have no visibility into the available quantity when you want to sell or use the product. All Orders has an alternate solution namely being able to have multiple vendors for each of your items. You set up your item vendors when you create your items.
Once you do this, you can view the vendors that supply a particular item from the Item Info screen or which YOUR items a vendor supplies from the Vendor Info screen.
You may also want to prevent users from ordering an item from a vendor that does not sell that item. You can restrict the items shown on the item grid drop by CHECKING 'Limit items for purchasing....' in Purchasing Preferences.