Here is some advice, you might want to check to see if the items you sell actually work. I understand that you don't make them, but at least make sure they work. Here is some more advice, try not to sell something for more than it's actually cost. For example, if a person comes in and asks for just a battery and you take off the tank and sell it for the same price as you would for both tank and battery, then you might want to rethink selling things. Besides, the battery you sold goes for less and it comes with the tank. Don't waste you time here, your just going to get the run around and told to buy something else unless you firmly ask for your money back.