Real Time Inventory at the end of day

[Guest]

My inventory contains 50 products with 15 to 20 different sizes, where I
manally enter the quantities in sheet 1 (on monthly bases) and then display
it to a table in sheet 2. I'm trying to update the inventory on another sheet
at the end of day by using two drop down list (product, size), then entering
an amount that was used or added to the inventory which will point and update
sheet 1.

 

[Guest]

so you want the drop down boxes to take you to the quantity cell of the
selected product,or????