Utilizing your Optimum Quantity, Maximum Quantity, and Reserved Quantity are all very important. These three are explained in some detail below:

Optimum Quantity: This number indicates the quantity of a card that you would like to have in stock. Opt Qty is required for a card to appear on your buylist. When actual quantity is less than your preset Opt Qty, that product will appear on your buylist.

Max Quantity: The greatest quantity of a single product that you would like your customers to be able to purchase in a single order. This is usually set to avoid a single customer from being able to buy out your entire stock of a product. Note that a product with a negative max qty will show up as out of stock.

Reserved Quantity: The quantity you would like to reserve for in-store sales. If you have 10 of a specific product, but want to always keep 2 in your physical store, you would set the Reserved Qty to 2, and only 8 would appear in-stock online.