假如你买了100万的房子，　首期只有５Ｗ，　借了９５Ｗ．

When ARM is reset, however the market is down, say 20%. Now your house is only worth 80W. The bank only wants to lend out 80% of the house value, that is 64W. unless you pay the 31W difference in downpay, it\'s very hard to get a refi.

I think this could be a potential big problem for the California Bay Area, because many people are already maxed out when they pay the downpay, and the huge house price asks a lot of cash to make up the difference if the house price is down.