Police Chief Dean Esserman of Providence, Rhode Island, said that for a time, his department saw a dramatic increase in copper thefts resulting from empty, foreclosed homes and the increased value of copper on the commodities market.

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The rich buy apartments and often leave them empty, treating them as a store of value.

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He said properties left empty for a long time often attracted "vandalism and fly tipping and drag down the value of the properties all around them".

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Though she declines to estimate her collection's value, Simoni will confess to having "about 200 frames, nearly all of them empty, " that cover the walls, and in some cases, ceilings, of her home.

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To avoid buying or giving an empty card, only purchase gift cards from secure displays or from stores that load the card with its value at the checkout, advises Mark Huffman of ConsumerAffairs.com.

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