At Prosper, the average rate for borrowers with a score higher than 720 is 9.4%; you post a loan request and set the maximum rate you're willing to pay, then lenders bid on it. Lending Club assigns grades based on your credit history and other factors and offers rates of 7.4% to 19% depending on your grade.
Cons: If your credit score isn't tip-top - 720 or better - forget it: The interest rate you'll pay will be downright ugly. At Prosper, for example, if your score is between 600 and 719, you would have paid an average of 16.5% recently; below 600, 35%. The lending sites also charge fees of 0.5% to 2%. And the amount you can borrow is capped, typically at $25,000.
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