Even if rents and vacancies don't totally collapse, the commercial real estate market may be in for violent upheaval, if only because there isn't enough available credit to deal with all the re-financings.

The New York Post runs down some of the grim numbers:

At the center of the worries is some $3.5 trillion in debt backed by everything from strip malls to offices and apartments across the nation -- the lion's share of which is badly underwater because this recession followed a five-year commercial property boom fueled by easy money and loose underwriting standards.

Now the owners of the less-than-full malls, apartment complexes and office buildings are succumbing to the worst economic collapse since the Great Depression -- because they can't refinance the debt.

The commercial debt securitization market is dead.

"Because there is no securitization the system cannot process the wave of maturities coming due," said Scott Latham, commercial property broker at Cushman & Wakefield.

"This is arguably the most important fact we're going to be dealing with. If there's no mortgage market that can feed the machine you're just not going to have deals," he said. "It's going to be years before we recover and even when that happens we're going to discover that we're in a new paradigm," Latham added.

About $1.4 trillion in real estate debt is set to mature over the next four years, with some $204 billion coming due this year alone.

From what we've heard, it's impossible to overstate how stingy commercial real estate lenders have become. Even projects with very solid tenants and no indication of a drop-off are having a hard time rolling over their debt.

Still, there's a difference between a homeowner going into foreclosure and a commercial real estate owner that still has paying tenants. Whoever receives the property will still be seeing cash flow, and there's a good chance it will have some value, rather than some house in the middle of nowhere, with no prospects of being sold, whose only realistic fate is a bulldozer.