Most homebuyers figure that their property taxes will be the same as those paid by the house's previous owner. That’s a common mistake.

They might be the same for a few months, or even a year, but eventually they’ll be recalculated. And when they are, they’ll most assuredly increase -- sometimes substantially.

But what if it's a new house that no one has ever owned before you? How can you know what the tax levy will be?

Most homebuilders make a good-faith estimate of the taxes their buyers can expect to pay. But some notoriously underestimate these fees to make their estimated mortgage payments appear more affordable.

Some builders go even further, basing their tax estimates not on the finished house, but on the value of the lot before a shovel was ever turned. And now a class-action suit protesting that practice has been filed in Florida.

Filed by a group of unhappy buyers, the suit charges the nation’s largest homebuilder, D.R. Horton, and its mortgage affiliate, DHI Mortgage, with a “deceptive scheme” that led to unexpectedly higher mortgage payments.

The buyers didn’t learn that their payments would be hundreds of dollars higher until after they closed on their mortgages and the loans were sold to new servicers on the secondary market, the lawsuit maintains. Once the new servicers took these loans under their wings, they adjusted the monthly payments so that they were based on the property tax assessment of the finished house -- not the empty lot.

In one instance, the suit alleges, a Horton homebuyer chose DHI Mortgage because the estimated monthly payment was lower than comparable houses with similar sales prices. But less than a year later, the new loan servicer conducted an escrow analysis that included all property taxes -- as well as back taxes to cover the previous shortfall.

The buyer’s monthly payment jumped nearly $1,000.

The lawsuit alleges that the builder and lender were "running a 'Monthly Payment Suppression Scheme' to mislead first-time homebuyers into thinking their total monthly housing costs would fit their budgets," said Jennifer Wagner, an attorney at the National Consumer Law Center (NCLC), in a prepared statement. The NCLC is co-representing the buyers in this case.

Only time will tell what becomes of the lawsuit. But it should stand as a warning to all homebuyers to make sure their property tax estimates are as accurate as possible. Buyers should try to determine on their own what their taxes will be. You can call the local assessor's office to find out, or you can ask for the tax rate and do the math yourself.

Realize, too, that your tax levy is not static. It's going to go up -- if not right away, then the next time the local tax assessor reviews your house. Housing prices are still rising, and property tax assessments are rising right along with them.

Part of the problem with underestimated property taxes lies with loan officers, who should make a concerted effort to determine what borrowers will pay prior to closing. Lenders should qualify borrowers for a mortgage based on the taxes at closing, not on what the seller is currently paying. But some don’t, and as a result, their clients' monthly charges will definitely go up, sometimes by hundreds.

Although you can pay your taxes annually on your own, most borrowers set up escrow accounts at closing to collect one-twelfth of their property taxes and homeowner's insurance fees each month. Then, when those charges are due, the loan servicer pays them on the homeowner's behalf, thereby removing the burden of coming up with that lump sum every year.

Eventually, the servicer will run an escrow analysis to make sure your payments are accurate. If not, it will adjust them accordingly. If you haven’t been paying enough since you took on your loan, you will be required to make up the difference.

You may be required to pay it all at once, or the servicer may agree to divide what you owe into equal amounts and add it to your monthly payment. Either way, the hit could be devastating to someone on a tight budget.

The tax collector will reassess your property at least once every three years. If values are rising in your area, you should expect your taxes to rise. But you also should expect your servicer to make annual adjustments to your escrow accounts.

If you disagree with either the tax assessment or your servicer, you can ask for a review. But in the end, there’s no way to avoid an increase, and it is your responsibility to pay it. It is one of the costs of owning a house.

To guard against unexpectedly large increases, some people pay a little extra every month into their escrow accounts. Others deposit money into a separate savings account so they’ll have funds set aside when the new bill arrives.

Buying a house is always a taxing experience. But when you are expecting a child, it turns into a “high-stakes, emotionally charged and biologically timed sprint,” says California real estate agent America Foy.

A 20-year veteran of the industry, Foy has worked with a number of pregnant buyers. In a series for RealtyTimes.com, Foy writes that the experience has taught him more about real estate than any seminar or licensing course.

"If you're expecting and looking to buy, you’re not just competing with other buyers," he writes. "You're racing against your own due date."

For Foy's clients, the second trimester "seems to be a sweet spot" for striking a deal: "If we can get into contract during the second trimester, things usually go smoothly."

Clients don't find the third trimester quite so sweet, he writes: "Every showing becomes an endurance test. Every flight of stairs feels like a mountain. The phrase 'appraisal contingency' can trigger a wave of nausea that has nothing to do with the baby."

A mother's "nesting instinct," Foy has learned, can be both a help and a hindrance: “It sharpens your focus on what truly matters. You stop caring about the open-concept layout for entertaining and start measuring bedrooms for cribs and calculating how many steps it is from the master bedroom to the kitchen for 2 a.m. feedings.”

But pregnant clients can be vulnerable to unscrupulous agents and sellers who can sense the buyer's urgency. “They know a pregnant buyer might waive contingencies or stretch their budget to secure the nest,” Foy writes.

Sometimes, the nesting instinct can actually turn dangerous. Foy writes that one expecting client, driven by the "biological imperative to secure a safe space," floated the idea of skipping the inspection just to get into the house quicker.

Whatever the cause, impatience "can turn rational buyers into deal saboteurs," he writes. Inspections are important tools for finding a house's problems before the buyer -- pregnant or not -- is committed to the place.

Sometimes, inspections find things that can pose serious health risks: mold, lead and animal feces, to name a few. These hazards aren’t necessarily deal-breakers -- not if you find them early. Rather, they can be used to negotiate price reductions, repairs or other concessions.

"Health hazards are expensive to fix, which means they’re powerful leverage points if you find them before closing," Foy writes.

In short, he says, “Your nesting instinct is powerful, but pair it with necessary additional inspections, and you get both the haven you crave and the financial protection you need.”

Now, the third trimester, Foy writes, is when “pregnancy brain meets mortgage bureaucracy.” Juggling pregnancy's many challenges while also comparing loan offers, reviewing contracts and negotiating contingencies can add up to what Foy calls “a perfect storm for decision fatigue and costly mistakes.”

Some soon-to-be moms don’t realize that their upcoming maternity leave is “a ticking time bomb in your loan file.” Even when the buyer has been preapproved, an underwriter sometimes panics about the looming income interruption.

"I learned this lesson the hard way, with multiple clients who got ambushed by lenders who suddenly decided unpaid leave was a 'material change' to their financial situation," Foy writes.

Here, Foy advises pregnant borrowers to disclose their situations to the lender from day one and to provide the following: a letter from HR detailing their company’s leave policy, including documentation of paid leave benefits (if any); a return-to-work commitment letter; and bank statements that show enough savings to cover the upcoming gap.

The real pressure cooker comes toward the end of the pregnancy. Things can really pile up. Picture Foy's list of hypothetical stressors: "Your rate lock expires in 45 days. Your baby is due in eight weeks. The appraisal is delayed because the appraiser got COVID. The title company found an easement issue. Your doctor just put you on bed rest.

"This is why front-loading the loan process matters," he writes. “Every day of delay (during this period) adds exponential stress to an already maxed-out system.”

He suggests creating buffer zones and cushions into every part of the process. For instance, lock in your mortgage rate for 60 days, not 45. Collect your loan documentation papers immediately. Schedule closing at least four weeks before your due date, and implement as many backup plans as possible.

The strain on every homeowner's pocketbook is showing up in all the usual places.

The typical indicators of homeowner financial stress -- mortgage delinquencies and foreclosure filings -- are rising across the land. Late payments across all credit tiers -- auto loans, credit cards, personal loans -- are increasing, too, even among the most creditworthy.

So what should a homeowner do to save their house when they land in dire financial straits?

For starters, don't hold your head in the sand, hoping that your lender won't discover you've missed a payment or two. The company will notice -- and will move quickly to protect its investment.

As soon as you think you might fall behind on payments, be proactive and call your lender. Most people don't.

"The biggest problem we have is that people don't call," says Dana Federspiel of ICE Mortgage Technology. "There are tons of ways to communicate with a lender, but most people don't use them."

Allen Price of BFI Financial Services, which manages loans on behalf of lenders, agrees. "When borrowers are more than 30 days late, they're afraid to even answer the phone," he says.

Price's advice: "Be communicative; be proactive."

But before you contact your lender, have your ducks lined up in a row. "Be prepared to explain your hardship," Federspiel advises. "You don't need to go into deep detail: just something like you're having health issues, or you lost your job."

Be able to document your monthly income, assets and expenses, including car loan payments, cable bills, telephone and utilities. You won't need to tell your lender how many cars you own or how much you spend at Starbucks, but the more complete your list, the better.

Working with your lender is beneficial to both parties. Lenders don't want you to lose your home any more than you do. It's expensive to take back a house, make it marketable and then sell it, so they'll work to figure out how to keep you in the house -- and as a customer.

There are numerous ways lenders can help you work through your difficulties, so explore all your options and ask lots of questions. "If you don't ask," Federspiel says, "you'll never know."

Depending on your situation, you may qualify for a forbearance plan, in which the lender can pause or reduce your monthly payment for several months.

There is no one type of forbearance plan; the length and term are based on your circumstances. But when the forbearance period ends, you'll be required to either pay back what you owe in one lump sum, extend the term of the loan to cover what you owe, or divide what you owe over a certain time period and pay it back in monthly installments.

If you experienced a permanent or long-term hardship and can no longer afford your mortgage, you may be eligible to have the loan modified. If so, your monthly payment could be cut by as much as 20%. Modifications can include a lower interest rate, extending the loan's term or reducing the principal balance.

A third choice is to repay the missed payments, either a portion at a time or over a set period of time, typically alongside your regular payment. And a fourth option is to renegotiate the terms entirely.

Everyone wants to save the roof over their heads. But the unfortunate reality is that sometimes you can't. Your financial burdens may be so heavy that no matter what you try to do, you are going to have to walk away.

Federspiel advises that you're probably overextended if you pay more than a third of your monthly income toward your mortgage. That's why it's important to consider your exit strategies -- the best ways to get out from under your debt with the least amount of damage to your credit and your family.

Generally, there are two ways to depart somewhat gracefully. One is to sell the house; the other, to deed the place back to your lender. Either way, you're pretty much controlling your own destiny rather than losing the place to foreclosure.

If you sell and make enough to pay off the loan, you can pocket any profit and move on. If you can't cover what you owe -- what's known as a "short sale" -- you'll need the lender to agree to accept the lower amount as payment in full.

If you just want out as cleanly as possible, you can simply sign the house over to the lender -- again, though, with the lender's permission. In return, the lender will forgive what you owe, and you can move on.

In discussing these choices, both of which will ding your credit record, try to do a little horse trading. Sometimes the lender will pay you to hand over your keys. In other cases, the lender may be willing to pay the cost to relocate your family to new digs.