The appetite is huge among companies like Kondaur Capital Corp., hedge funds and investors to buy shaky mortgages, credit-card debts, auto loans and even payday loans from lenders eager to cut their losses. So far this year, nearly $10bn in troubled mortgages has changed hands, according to Private National Mortgage Acceptance Co., or PennyMac, a mortgage-loan buyer started in 2008. Such loans often sell for just pennies on the dollar, with the buyers hoping to make a profit by restructuring the loan, selling it to someone else or, in the case of mortgages, foreclosing if all else fails.