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I, personally, would require that the dealer inform HS about this arrangement. I would want a signed form from HS saying that they as the manufacturer would back up this deal. I have seen, many times, deals like this between dealers, sales staff and customers . If something were to happen, and the sales person or heaven forbid the dealer are gone (out of business), the factory won't do anything about it. Most companies that I know don't provide full warranty on blems or damaged product. From my experience, if it is blistered in one area, it is only a matter of time before they crop up in other areas of the tub. Being left in the sun may be the cause, but I would put my $ on problem occurring during the molding process of the shell. Just my two cents
I would just make sure the paper work did not say 'AS IS' anywhere.
Jump on it.