The point is that every transaction involves tradeoffs, and a slightly less desirable house at a far more agreeable price can make the difference between building wealth and overextending yourself.

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That difference is reflected both in price and flexibility at Chegg.com, which offers more than four million books in various formats.

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As the internet and profiling technologies become more common, many expect that buying histories will make a difference to the price you pay for goods and services.

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The council document said following more detailed investigations a "variation" - or difference between the agreed price list, called the the "schedule of rates" - and the actual amount charged by MITIE was found.

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As construction proceeds, the difference between the price of gas and the price of electricity widens and narrows, giving Duke the opportunity to sell more of the expected output if the price rises or sell output in future years to lock in profits on electricity it has yet to generate.

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