Amazon does not regard itself as a storage facility and their storage prices reflect that, especially during the fourth quarter when rates increase.  If you are using Amazon to sell your products or using Fulfillment by Amazon FBA you are likely paying too much for Amazon to store your goods.  Ideally you would want to store only what Amazon needs to fulfill your orders and then ship new products to Amazon to replenish your stock.  One way to do this is to have a fulfillment center or 3pl store your products at a lower cost and ship them to Amazon as soon as your Amazon stocks need to be replenished.  In order to do this you will need to make sure you understand and can forecast your Amazon sales in order to make sure that your stock levels are not completely depleted.  You should also take into account unexpected delays or events, especially near the holiday season as sometimes Amazon does not have the capability to quickly receive product and distribute it to it's warehouses.  Store your product at a fulfillment center or 3pl will also give you the flexibility to have them fulfill your website orders.  This can usually be done at a lower cost than Fulfillment By Amazon and can be more customized to reflect your brand