While each of the four major card networks offers some form of complimentary rental insurance and extended warranty coverage to their cardholders, eligibility for coverage as well as the quality of coverage provided varies significantly by network.

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Stores like Best Buy typically don't garner massive profits from just selling the snazzy new LCD or LCoS televisions, but "around 50 percent" of the extended warranty's pricetag goes straight to their pocket, and rarely do consumers need the coverage until after it's up.

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