Hi, 

    In this case, you can use Product Variants feature. You can create a product as Flavored Drinks and add all the six flavors as variants of the product for which you can specify different prices also. However, this in turn will create six different products in POS that represents each of the flavor. 

    This is because, when you make an order for the particular product flavor, the stock information will be recorded respectively. For eg., Into a purchase order, you may place an order only for 2 flavors, were as in POS if you try to process other than that flavors, then that will be processed based on the stock count available with respect to the flavors ordered. 

     Also, the Vendors list, that is available into Products -> Inventory, is generally to define the price of the product based on different Vendors. So, whenever you select the particular vendor code into the Product Line in Purchase order, it will default the price specified, however it will replace the Product Name, instead of the Vendor Code.