If I am not mistaken, with its cloud-based computing, Amazon cannot separate a book sale transaction from a data cloud rental without incurring significant additional costs in redundant and unnecessary IT infrastructure.

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There are, of course, exceptions to that rule involving items rented for very short periods or where the rental includes a lot of additional service, but that is not what is going on in this situation.

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Many people who lost their homes due to foreclosure have swelled the rental pool and that sucked up additional inventory.

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The company gets money from both parties: Hosts are charged a 3% fee when they receive a successful booking, while travelers pay an additional 6-12% on top of the rental fee.

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Silver Bay intends to use the net proceeds of the offering to purchase additional single-family properties, to renovate such properties for rental to tenants and for working capital.

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In a nice touch, drivers age 21 to 24 don't pay additional fees to use Zipcar, On Demand or Car2go, while most traditional rental companies charge younger drivers a premium.

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Some upscale apartment rental services happily provide their guests with concierge services on demand (and often at an additional cost, but not always).

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