The latest sales numbers from the nation's multiple listing services are in, and housing is looking good.

As of May 1, only nine of the 100 core-based statistical areas (CBSAs) with more than 500 sales in the previous three months saw prices decline. The other 91 booked higher prices -- some quite significantly.

Overall, according to data supplied by Pro Teck Valuation Services of Waltham, Mass., the average mean price of the hundred most active CBSAs was up almost 12 percent from the same period a year ago. CBSAs are defined as "micropolitan" areas of at least 10,000 people who are tied to an urban center by commuting.

The average median nationally as of May 1 was $212,869. At the same time last year, it was $190,278.

But throw those numbers out with the morning trash. Since all real estate is local, the national median is useful only as a headline. What's more important to buyers and sellers -- and even owners -- is knowing whether the real estate market is rising or falling where they live.

Much more valuable in gauging the path of house prices is price per square foot, which is the great equalizer. Whereas other measures are often influenced by an unusually high number of sales at one end of the price spectrum or the other, the median price per square foot evens things out.

By normalizing for swings in the type and price of houses sold, the price per square foot -- or PPSF -- represents a truer market snapshot and is a better way by which all houses can be judged against one another.

That alone makes Pro Teck's figures more meaningful. And giving them ever greater credence is the fact that they are the most recent.

Whereas other measures you might read or hear about are often up to six months old, the numbers supplied to this column by the Massachusetts valuation company are collected from the country's 850 multiple list services and updated daily. You can't get much more current than that.

With that as a backdrop, let's take a peek at what's happening in selected places around the country.

The latest leader in the quarterly price dance is Atlanta. The median PPSF of a house sold in the last three months in the Atalanta-Sandy Springs-Marietta CBSA jumped 41 percent, from $46.64 a year ago to $65.74, while the median price rose 43 percent, from $95,000 to $136,000.

Atlanta's PPSF numbers compare quite favorably to the national average median, which was $115.91 per square foot as of May 1, an increase of nearly 11 percent from a year ago.

Detroit was another big gainer. The median PPSF there rose almost 33 percent, from $38.30 to $50.79, the lowest PPSF of the hundred most active markets.

Of the eight next best-performing CBSAs, one is in Arizona, another is in Florida, two are in Nevada and four are in California. And in all eight, the average median jump in square foot price was from 22 percent to 28 percent.

The most expensive market is San Francisco, at least pricewise. There, the median price rose an astonishing $180,000, from $735,000 this time last spring to $915,000 as of May 1, nearly a 25 percent gain.

And as a result, the per-square-foot price in the Bay Area rose 22 percent, only the 11th-strongest gain, from $448.61 to $545.60.

Down the Pacific coast: In Los Angeles, the PPSF rose 18.91 percent during the period, from $229.28 to $272.63, while the PPSF in San Diego rose 17.89 percent, from $200 to $235.77.

Moving across the country, the median PPSF was up 7.55 percent, to $76.82, in Houston, and 7.51 percent, to $85.19, in Dallas. In Chicago, it was up 1.71 percent, to $95.87.

In Florida, the median was up strongly across the state. In Orlando, it was up nearly 19 percent, to $82.59. Miami's PPSF was up 17.4 percent, to $112.74. In Tampa-St. Pete, it was up 15.2 percent, to $83.98. And in Sarasota, it rose 13.2 percent, to $66.71.

Are you ready to bet that the great housing recession is finally over and that values are rising again? If so, some of the nation's largest institutional investors are ready to roll the dice with you.

Pension funds, endowment portfolios and the like don't typically invest in residential real estate, which is the world's largest asset class. But given their long-term horizons, housing is considered a natural fit. And now there's a new investment vehicle that aligns their stash of cash with creditworthy homebuyers.

It's called REX HomeBuyer, and it is a form of shared appreciation. But it's not a mortgage, nor is it down payment assistance. "It's not debt of any kind," says James Riccitelli, co-CEO at firstREX in San Francisco. "It's an innovative solution that helps responsible buyers bridge the funding gap."

REX HomeBuyer is an equity investment by private real estate investors that pays off when you sell the house. If there's a profit, fine, you hand over a pre-arranged share of the gain. And if there's a loss, REX shares in the loss.

"We invest in the home at the same time the buyer does," says Riccitelli, "and we expect to make a profit or loss at the same time the buyer does."

Here's how it works: Say you want to buy a house that sells for $500,000, but you're a little short on the requisite 20 percent down payment ($100,000 in this case). FirstRex will provide up to half of the down payment, or $50,000.

In return, you typically agree to give the company 40 percent of the change in value when you sell.

So, 10 years from now, let's say the home is now worth $600,000. If you sell, firstREX gets its original investment of $50,000 plus its share of the change in value, or $40,000. You receive the rest.

But by then, you've paid your $400,000 mortgage down to $325,000, so your payoff on your original $50,000 investment is $185,000. That's $60,000 from your share of the appreciation, $75,000 you built in equity by paying down the loan and your original $50,000 down payment.

Better yet, during the time you owned the house, you made no payments to firstREX, and your 20 percent down payment prevented you from having to pay costly mortgage insurance.

Now suppose the housing gods turn angry again, and your house is worth only $400,000 when you sell in a decade. The mortgage payoff is still the same $325,000, leaving the proceeds to be split 60-40. So firstREX receives $10,000: its original $50,000 investment, less $40,000, which is its share of the $100,000 loss. You get $65,000.

Recapping: When values rise, says Riccitelli, "the buyer benefits from using our money. We make a healthy profit, but so does the buyer, typically as much or more than we do."

And when values decline? "The buyer benefits from the use of our money and actually makes a profit on us by paying us less at the end than the amount we invested," the long-time finance industry executive says. "An even better deal for the buyer."

Even when there's no change in value, he adds, "the buyer benefits from using our money at no cost. And in all three situations, we enabled the buyer to purchase the home in the first place."

"The buyer benefits no matter how the outcome plays out," says Riccitelli.

The REX program is only a few months old, and only about 20 deals have been made to date. So it's way too soon to tell whether this is the next great thing in housing finance. But Riccitelli says his group has trillions of dollars to invest in an asset class in which they now have a zero allocation.

FirstREX itself is a real estate equity investment firm founded in 2004 to focus on developing financing products based on equity instead of debt. Its shareholders include world-class institutional investment firms and financial institutions as well as senior management executives.

Riccitelli won't reveal his backers' identities. "We are bound by confidentiality provisions," he says. "But they are very, very serious people -- including myself. And they are lining up" to put their money in housing.

Together, they have spent upwards of $20 million to build and develop the REX HomeBuyer program over the last eight years. "They've done a lot of research," Riccitelli says of his anonymous investors. "They have a huge confidence in the housing market."

They are patient, too. They promise to wait until you sell, even if they have to wait 30 years. And they promise not to ever sell their share of your property to another investor.

Of course, REX isn't for everyone. Folks with shaky credit and income need not apply. You've got to be short on cash, not credit. You can even have enough for a full down payment on your own, but for one reason or another, you may be uncomfortable spending it all to buy a house. Maybe you want some left over to buy new furnishings or make some improvements.

Whatever the case, you'll still need a first mortgage. But because REX is structured in such a way that it is always subordinate to the mortgage -- and because it is in a first-loss position along with the buyer -- lenders are likely to consider a loan a safer bet with REX in the deal.

REX ends when the buyer sells or when everyone on the title passes away, whichever comes first, subject to a maximum term of 30 years. But the buyer can end the agreement at any time without selling by buying out the investor.

If that happens, the agreement calls for REX to hire an independent third-party appraiser to determine the home's value, and you pay an amount equal to the company's original investment plus any profit that would have been earned had the place sold for the newly appraised value.

One caveat, though: This is not a short-term funding solution. If you sell within the first three years, there is an additional charge.

Financially strapped homeowners who are close to foreclosure may want to face the music now rather than continuing to struggle with their monthly payments. There's a high probability of losing the house anyway, even with the government's help.

According to a new report, people who take advantage of a key federal program to modify their mortgages in an effort to save their homes are defaulting "at an alarming rate."

The report from the special inspector general for the Treasury Department's Troubled Asset Relief Program doesn't say why an inordinately high percentage of owners who take part in the Home Affordable Modification Program, or HAMP, are unable to maintain their loan modifications. The report only says that the longer owners remain in the program, the more likely they are to default again.

Even with permanently reduced loan payments, the number of owners who are "redefaulting" is rising, the inspector general says.

At the end of the first quarter of 2013, the report found, nearly half of the oldest of the HAMP modifications, from the third and fourth quarters of 2009, are going back into default.

Specifically, 46 percent of the HAMP mods made in the third quarter of '09 redefaulted and 39 percent flunked out in the fourth quarter. Even mods from 2010 had high failure rates, ranging up to nearly 38 percent, the report says.

As of March 31, of the 1.28 million owners whose loans were modified under HAMP, more than 312,000 have gone into default again. And when that happens, the consequences are severe.

Owners who cannot sustain their reworked loans and fall out of HAMP are left with the terms of the original mortgage. And as such, they are responsible for making up the difference between the original loan payment and the lower HAMP loan payment.

Not only can the back payment be substantial, the inspector general advises, but already-distressed owners can be hit with late fees on both the principal and interest that weren't paid during the modification period.

In some instances, the report cautions, redefaulting borrowers can end up owing more than they did before their loans were modified.

The Obama administration's signature housing support program, HAMP was created in 2009 to help owners avoid preventable foreclosure by encouraging the companies which administer their mortgages -- so-called loan "servicers" -- to find ways to lower their payments.

Under the program, which was recently extended until Jan. 1, 2016, borrowers with loans made prior to 2009 whose monthly payments for principal, interest, taxes and insurance are more than 31 percent of their gross income are eligible. Generally, servicers reduce the borrower's interest rate or extend the loan term to bring the payment down to an affordable and sustainable level.

As a last resort, but only with the agreement of the investor that owns the loan and is the ultimate recipient of the principal and interest you pay every month, servicers may also forgive some of the amount still owed on the mortgage.

But HAMP doesn't subsidize troubled borrowers. Rather, it provides financial incentives to mortgage servicers that work with borrowers. More than $4 billion of the $7.3 billion in federal funds spent on housing support programs during the housing crisis was spent under HAMP alone.

That raises the question of whether some servicers may be modifying loans they know will eventually fail anyway just to earn fees from Uncle Sam. No one seems to have addressed that issue. But previous research discovered some interesting findings.

For example, a study a few years back from the Federal Reserve Bank of New York found that, pre-HAMP, servicers focused on particularly risky borrowers with lower credit scores, higher debt-to-income ratios and loans with higher original loan-to-value ratios. Thus, the people most likely to fail with or without some kind of relief.

The New York Fed also found that the greater the payment reduction, the less the rate of recidivism. But many loan mods don't lower the payment. Rather, many result in higher payments and higher balances because the payments owed plus any penalties and fees are added to the outstanding balance without changing other terms of the loan.

On the other hand, the study found that the lowest redefault rates occurred when the payment reduction was paired with principal reduction. In other words, the servicer agreed to forgive some of what was owed. When their principal is reduced, the study found, problematic borrowers are four times less likely to default again.

Other studies from the University of North Carolina and the Boston and Atlanta Federal Reserve Banks had similar findings: There's a high correlation between redefaulting and loan mods in which your payments are stretched out and your debt is deferred -- but not reduced.

So the message for underwater borrowers considering a loan modification is this: Unless your servicer offers to rework your loan in such a way that you no longer owe more than the house is worth, think hard about what you are doing.

Is there a real chance you can save your house? Or are you merely putting off the inevitable?