[quote=" I mentioned maybe the contractor could build one for less, and the sales lady said then you void the warranty.
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Ridiculous! We once bought a new mattress from Penney's. They tried to sell us a very expensive mattress cover, and we didn't buy it at the same time. After thinking about it we bought it later that same day, and before the mattress was delivered, but they told us we had voided our warranty by not buying it at the same time. That was the end of us shopping there.