Reverse mortgages are similar to other home-equity loans in that they enable seniors to obtain a loan based on the debt-free portion of the value of their home.

Reverse mortgages, however, are first mortgages, so you must have enough equity to at least pay off the original first mortgage before drawing extra cash.

Generally, to qualify for a reverse mortgage, you must be 62 or older and own your home outright or have enough equity to pay off the original first mortgage.

The loan principal and interest are repaid later, from the proceeds of a sale when you move or die.

The variations on reverse mortgages include:

* Tenure. You get monthly payments from lenders for as long as you live in your home.

* Term. You receive monthly payments for a fixed period before, say, a pension takes effect or you sell your house with plans to move elsewhere. You may or may not have to settle up when the payments stop, but you will continue to owe interest on what has been borrowed until you do.

* Line-of-credit. You withdraw money only as needed.

* Lump sum. You initially withdraw one lump sum.

* Combination. Some programs enable you to combine two variations, for example, withdraw a lump sum first and monthly payments later.

Because of the complexity of the programs, representatives of local and state seniors' organizations advise that you seek independent counseling from attorneys, accountants and special reverse-mortgage counseling programs before you seek a reverse mortgage.

Consumers Union also recommends mortgage counselors approved by the Department of Housing and Urban Development.

The Consumers Union offers these additional tips:

* Don't take a reverse mortgage if you want to will your house to heirs or if you have another, less costly way to reach your financial goal.

* Be aware that income from reverse mortgages can affect your eligibility for certain public benefits including Medicaid, Supplemental Social Security Income and Medi-Cal benefits.

* Shop around and compare. Pay particular attention to origination costs, loan and brokerage fees and "shared appreciation" and "shared equity" agreements that grant the lender extra fees based on your home's value.

* Never sign a reverse-mortgage contract without reading and fully understanding every detail.