We have been using various versions of SAGE for over 5 years.  We've now decided to set up an Inventory in Sage.  I have entered all of my inventory items. But - a lot of the items we have in stock have been purchased prior to setting up inventory in Sage.  How do I utilize the inventory items for items purchased prior to setting up the inventory.  For example, we have 20 of #16 Stainless Steel Clamps rolling around in the Service Truck.  When I go to enter my sales invoice I don't have a purchase order for the 4  #16 SS Clamps used on the order so it tells me I am using more than I have.  Can I use the "Adjusting Inventory" to enter the number I have on hand?  I am just plain confused on this one.

Thanks
Gwen