Additionally, the a complex of four buildings, had a $2.5 million underlying mortgage.

"They're playing the market, even with their underlying mortgages," he continued.

In doing so, those owners paid down $2.3 million of the underlying mortgage.

The first, he said, is that most co-ops have an underlying mortgage on the building.

The maintenance is very low because the building has no underlying mortgage.

The interest rate on our underlying mortgage is close to 9 percent.

The underlying mortgage on the building would help hold initial purchase prices down.

Lenders have become less willing to increase the size of an underlying mortgage because values for the most part are no longer rising.

But the bank that held the underlying mortgage went out of business.

Such steps are not possible in condominiums, however, because they have no underlying mortgages.