Warehousing means storing the merchandise that you sell. While this may seem like a simple thing to do, remember that you will need to be able to quickly pull merchandise once an order is placed. That means that, while you do not need to display merchandise in the same way as a retail store, you still need to be able to see where each item is and easy reach it. Therefore, you will need to buy or design shelving that maximizes storage space while giving you easy access to the merchandise.
Storing merchandise depends a lot on what you sell (how big, how many items) and much inventory you keep in stock.
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Thoughts on Proper Warehouse Layout