Know what kind of mortgage you have

Dollar bills shaped like a house

Surveys suggest a shocking number of homeowners -- as many as one out in three -- don't know if they have a fixed-rate or adjustable-rate home loan.

If you aren't sure, dig out your mortgage papers and check. A big, new bill landing in your mailbox is no way to find out.

This is especially important if you live in a state like California or Nevada, where ARMs account for 40% of all outstanding mortgages, or have a subprime loan, which almost always has adjustable interest rates.

Anyone with an ARM must know when the payments begin rising and by how much. Increases of 10% or 20% are common when these mortgages reset.

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