To solve this problem, many sellers' agents offer to cut their own fee while still offering the full price to the buyer's agent.

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The listings are much more detailed than what typical commercial real estate sites provide. 42Floors, which right now is live in San Francisco, provides listings to agents for free and takes a fee on transactions.

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It charges a flat hourly fee for sending a team of agents onto the street, but Chief Executive Simon Rydings, would not say what that was.

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Stockbrokers and insurance agents generally work on commission, while Registered Investment Advisors tend to charge either an hourly fee or a percentage of assets under management as compensation.

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Rental agents are motivated to sell you a house rather than rent you one so as to collect a higher fee.

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