You Can't Sell What You Don't Have: Whether your inventory is sitting in your home, a retail location, a warehouse or a drop shipping location, you need to be aware of what you physically do and do not have in inventory (or have access to) before you can make a sale. In some cases, you will also need to know what you can and cannot sell legally based on federal or state laws. You will also need to know about interstate sales, especially in the mail order business. Finding suppliers that you can count on is a major step in establishing any type of sales business. Learn as much as you can about a vendor before ordering from them. Don't be lured by great prices if the reputation of the vendor is shady--do your research. By joining organizations, you can find out which vendors are winners and which ones may sell you down the river.