When Rodrigo Lopez snuck into this country 25 years ago, there wasn’t the controversy there is today about undocumented immigrants. He put down roots, becoming a homeowner in 2004.

Lopez (not his real name -- he’s actually a composite made from the stories of numerous immigrants) never had a Social Security number, which most homebuyers use to prove their identities to lenders. Instead, he used an Individual Taxpayer Identification Number, or ITIN, issued by the Internal Revenue Service to identify himself.

ITINs are issued to taxpayers who are not eligible to obtain Social Security numbers, regardless of immigration status.

At times, Lopez worked 60 hours a week. He paid taxes, just like everybody else. He paid his bills on time, always in cash because he didn’t have any credit cards, and put a couple of kids through college. And he never, ever got into trouble with the law.

Lopez bought his house with a mortgage from a Midwestern bank under a pilot program spearheaded by the Mortgage Guaranty Insurance Co. That initiative fizzled, largely because investors wouldn’t buy loans in which their borrowers’ legal residency hadn’t been proven.

Nevertheless, hundreds, if not thousands, of undocumented immigrants are still using ITINs to buy houses.

Government figures indicate that more undocumented immigrants are leaving the United States than are entering, but nobody knows for certain how many remain here. The Federation for American Immigration Reform (FAIR) says 12.5 million people who’ve entered the country without authorization, or remained after their authorizations expired, still reside here. (According to the FAIR website, the group seeks “lower levels of overall immigration” but says that “immigration, within proper limits, can be positive.”)

Likewise, there is no official count of the number of lenders willing to write mortgages on behalf of undocumented immigrants. But Scotsman Guide, a monthly mortgage industry publication, lists 18 lenders who finance homebuyers on the basis of ITINs.

The IRS does not verify or validate information supplied during the ITIN application process, and neither do lenders who accept ITINs as identifiers.

Other than that, though, ITIN lenders check out potential borrowers -- vigorously.

“Nobody is trying to fool anybody,” says Raymond Eshaghian, president of Greenbox Loans, a Los Angeles-based lender that prides itself on the concept of “out-of-the-box” underwriting. “They have to qualify just like everybody else.”

Among other things, Greenbox verifies a minimum of two years’ tax returns and the applicant’s country of origin. “Just like the old days, you have to make common-sense lending decisions,” Eshaghian says. “Each application is analyzed, borrowers have to show they have the ability to pay, and you have to meet compliance requirements.”

Greenbox also charges for additional risk, currently 7 percent for a 30-year fixed-rate loan. For that, customers with ITINs can borrow up to $600,000 with 10 percent down if they have a credit score of 620 or higher, or 25 percent down if they have no score. But they need only 5 percent of their own money; the rest can come from family gifts.

Las Vegas-based Alterra Home Loans also charges higher rates to ITIN users, and wants 20 percent down. The company’s requirements include two years’ employment in the same or similar line of work and tax returns using the borrower’s ITIN for the preceding two years.

First National Bank of America in East Lansing, Michigan, offers ITIN loans in all 50 states. It wants at least 15 percent down (gift funds are allowed) and borrowers must document their income with tax returns or bank statements.

Not everyone favors allowing undocumented immigrants to become homeowners.

“It’s a form of insanity,” says Dave Ray, a spokesman for FAIR. “Any program that incentivizes illegal immigrants runs counter to federal law and undermines national security and public safety. If someone is here illegally, there has been no criminal background check or any other checks. They are a complete unknown.”

Eshaghian, however, says his ITIN clients are “excellent borrowers” and “very responsible.”

To that point, Guadalupe Credit Union in Santa Fe, New Mexico, reports that its delinquency rate among ITIN borrowers with auto loans and mortgages is 1.24 percent, compared to 1.85 percent for its entire portfolio. And the Latino Community Credit Union in Durham, North Carolina, which has 86 percent of its mortgage portfolio in ITIN loans, says its delinquency rate is 1.16 percent.

Both figures are far under the industry average of 4.63 percent as of this year’s first quarter, according to the Mortgage Bankers Association.

Eshaghian of Greenbox says he understands there is “a lot of sensitivity” surrounding undocumented immigrants.

“You can say all kinds of negative stuff, but you have to look at these families closely,” he argues. “They are not criminals. They are not trying to take advantage of this country.”

As far as he’s concerned, “it really says a lot when people who could really hide” come out of the shadows. “They could continue going under the radar, but they live here just like me and you,” he says. “And they want to do the right thing.”

People searching for newly constructed homes on the popular Zillow and Trulia websites are not likely to find all the places that are available.

Zillow bills itself as “the largest, most trusted and vibrant home-related marketplace in the world.” But in early 2016, the Seattle-based company quietly stopped publishing listings from some of the country’s largest builders unless it was paid by the builders to add them.

Zillow, which owns Trulia, has contracts with most of the country’s 700-plus multiple listing services (MLS), agreeing to post every house listed by realty agents and entered into an MLS, whether resale or new construction. As long as agents opt in, their MLS listings will be sent to Zillow.

But the company has reversed course when it comes to new homes, saying that builders that sell more than 150 houses a year have to enter their listings directly with the site as part of its Promoted Communities program.

The company maintains that its motives were pure, in that would-be buyers craved more information about new communities and neighborhoods than what was available from the local MLS. By entering their offerings directly, builders could include as much information as they wanted -- for example, floor plans, community amenities and lot availability.

“We launched with the consumer in mind,” said Vice President of Builder Sales Lucy Wohltman, “allowing them to discover new construction listings more easily and earlier than ever before.”

But the policy change also became another revenue stream for the company. Most builders don’t put up anywhere near 150 houses a year, but many do. And by charging them $500 per subdivision per month to have those houses listed, Zillow stands to rake in millions for something it was once doing without charging builders anything.

The company won’t release the number of builder participants, or how much it earns from the program, but Wohltman says some 10,000 communities are displayed on the site.

Most builders contacted for this article refused to talk about the Zillow initiative, opting to sidestep any controversy. There is good reason to stay on the company’s good side: Most homebuyers today start their search online, and Zillow is a go-to site. Most builders seem to have capitulated to Zillow’s effort to squeeze money out of them.

But some builders have balked. Beazer Homes -- the 11th largest, according to trade publication Builder -- has said no, arguing that it has enough leads coming in from other sources.

The numbers tell the dissidents’ story. A builder who operates in, say, 12 different communities would pay Zillow $6,000 a month to list its houses. That kind of money puts a severe crimp in marketing budgets, or else becomes a cost passed on to buyers.

According to the National Association of Home Builders, only 8 percent of all builders sell more than 100 houses annually. Zillow asserts its program impacts “less than 10 percent” of the builders on its site.

But Texas-based Ben Caballero of HomesUSA finds that claim somewhat suspect. Pointing out that 10 percent of the country’s nearly 50,000 homebuilders erect some 90 percent of all houses, he says the change is nothing more than a “pay for play” ploy on Zillow’s part.

Caballero works with more than 60 Lone Star State builders. He lists their houses in their local MLSs, and when a client sells a house, he is credited as the listing agent. At last count, he found that 27 of his builder-clients in the Dallas-Fort Worth area, and three in Houston, had refused to list directly with Zillow. Together, they build in 369 different communities. Two more clients have canceled their subscriptions to the initiative, and one is “on pause.”

Caballero has no quarrel with Zillow’s desire to provide consumers with more information. But he is angry about how the company went about the initiative. He didn’t find out about the program until one of his builder-clients called to ask why his houses weren’t listed.

“Zillow didn’t tell anyone -- not brokers and not the MLSs,” Caballero said in an interview. “They did it covertly. Only builders were told listings would be taken down” unless Zillow was paid directly.

“I don’t understand why they were so clandestine about it,” he added. “I have been telling my clients that when they list through me, their houses will be seen on all aggregation sites such as Zillow and Realtor.com. So I have been inadvertently misleading them because I was unaware of the change.”

Caballero isn’t the only one angry at Zillow; so is Georgia’s Kendall Butler of FLI Properties. She wasn’t told about the program, either, and only found out about it when the leads she had been receiving from Zillow slowed to a trickle.

Butler checked and discovered that Zillow had taken down listings from all three of the builders she represents, even though only one met the 150-home threshold. “They removed all my builders’ listings without telling us,” she said. “I called five times and I never heard back.”

The agent sees the program as a “money grab” that goes against two of Zillow’s claimed core values: transparency and putting the consumer first. None of her builders see the value in the program, she said, so they now have no listings on either Zillow or Trulia.

“They tried to force them in by removing all their listings. It seems like blackmail to me,” Butler said.

Zillow’s Wohltman said she “wouldn’t use the word ‘pushback’” to describe these grievances, adding that “it’s more like ‘confusion’” on the part of naysayers. “Builders can still publish their listings through their MLSs, but they will be buried (among listings for resale houses) if they don’t come through the paid platform,” she said.

Caballero said he contacted four MLSs in Texas, questioning “whether they had a unilateral right not to push (listings) through to Zillow,” he said. “But they said they had nondisclosure agreements with Zillow and couldn’t comment.”

Caballero also maintains that Zillow is haphazard when it comes to listings -- publishing some, but not all, builders’ offerings. One of his clients says the site lists 45 of his houses for sale, but not 27 others, and incorrectly lists 40 as “not for sale.”

Faster is often better -- but not always.

Modern technology has vastly shortened the time it takes to qualify for a mortgage and close on a home. The internet continues to streamline the real estate process with new programs that improve efficiency at a blistering rate. But there are still some real estate transactions where speed can cause an uncomfortable squeeze.

The need for speed is everywhere in real estate and finance these days. Quicken Loans’ Rocket Mortgage, for instance, advertises a loan approval in minutes. And the length of time houses are on the market gets shorter and shorter every year.

But does all that speed leave enough time for buyers to do what they need to do?

First, let’s look at the ever-shortening time spans.

According to real estate company Zillow, last year saw the fastest pace ever for house sales. A typical abode was on the market for just 81 days, with many markets coming in much quicker than that: 41 days in San Jose, for example, and 43 in San Francisco.

Ever-more sophisticated technology has helped speed things up, but the acceleration has mainly been caused by hyper-hot housing markets, where decent houses for sale are few and far between.

According to Zillow, “the fastest-selling month on record was June 2017, when the median valued home took 73 days to sell, including closing.”

“Tight inventory accounts for much of the crunch,” the firm reports. “The number of homes for sale has fallen on a year-over-year basis for 37 consecutive months, leaving fewer options for buyers -- which contributes to higher prices.”

Many people in the real estate business are happy that things are speeding up so rapidly. Jonathan Corr, president and chief executive of mortgage software firm Ellie Mae, thinks the efforts of tech firms like his may shrink homebuying timelines even more.

Zillow pegs the average homebuying transaction as taking four to six weeks from contract to closing, but Corr says it could soon be even faster. He notes, “If you’re a consumer, you want the process to be shorter.”

No doubt sellers and real estate professionals are happy to be getting their money quicker. And borrowers refinancing their loans want to see their transactions close ASAP so they can lower their rates or tap into their equity right away.

But what about folks who are selling one home and buying another? Or merging two households into one?

They can usually only move so fast, no matter how quickly the lender is ready to hand over the money. And if they can’t get everything done in time, everyone else is stuck in neutral.

Until technology vendors devise an electronic way to physically move possessions from one home to another, for example, buyers are going to have to make their moves the old-fashioned way. And that can take time. Atlas Van Lines, for instance, recommends allowing two months to execute a move properly.

The company’s list of the myriad details involved can be a little daunting. Its recommended tasks begin two months before moving day, and cover everything from measuring furniture to be sure it fits in the new place, to

turning utilities off in the old home and on in the new. You’ll also need to make arrangements for pets, get your deposit back if you’re a renter, and on and on.

In other words, most moves take time.

Still, technology doesn’t have to be the bad guy, squeezing you into an uncomfortably quick move, according to Joe Tyrrell, Ellie Mae’s executive vice president of corporate strategy. For one thing, it can help your lender be more efficient in ways that will benefit you.

Most lenders sell their loans off to investors in the secondary market, and the numerous investors who buy loans all tend to have different requirements. While that doesn’t seem to matter on the consumer side, buyers may be annoyed if they are required to fill out extra documents before closing because your lender switched to a different investor. But Ellie Mae, among others, has software that can remove that irritant.

Another Ellie Mae program makes for a more pleasant borrowing experience: It analyzes applicants’ behavior and predicts when they are most likely to initiate contact with their lenders. That way, lenders can make sure they are available at those particular times.

“This lifts (borrower) confidence, and fewer loans fall out of the pipeline,” Tyrrell says. “There are plenty of competitors in the mortgage space. If it’s not high-tech, people will go someplace else.”

-- Freelance writer Mark Fogarty contributed to this report.