Should I have set something up to track the above behavior that happens prior to a purchase event? If yes what is the recommended method? I have tried a few ways I thought tell me but as of yet no luck.
Did you try setting product merchandising events to solve this? I would set 2 numeric events (item Quantity Added, item Quantity Removed) equals to item quantity added or removed and set it as merchandising event in product string on the cart page each time a unit added and removed.