NEW YORK (CNN/Money) – You've heard the horror stories. An unwitting homebuyer kisses a huge down payment goodbye, signs a sheaf of documents and moves in – only to spend their free time and income warring against a leaky roof, rampant mold or a flood-prone basement.

In short, they bought a real estate lemon.

Problems vary from lemon to lemon, of course. And most often you'll have some sense of troubles plaguing a property before you buy - compliments of the home inspector. But in today's hot market, where price wars put problem-free houses out of reach for many, a growing number of homebuyers are walking into money pits without thinking twice.

"People fall in love with homes, but don't get the facts about them. It's like a blind date," said Richard Collier, CEO of ChoicePoint, which issues CLUE reports. "They have no idea what they'll get."

Dream house or not, you might consider moving on if the inspection report flags problems with the home's structure or foundation, roof, mold or pet odor.

Here's how much it can cost you:

The leaky roof A roof replacement could cost between $5,000 and $20,000, according to Nancy Knott, a Realtor in Rancho Bernardo, Calif. When you take a tour, keep an eye out for signs of leaks. Ask how old the roof is. And have your home inspector tell you the roof's life expectancy.

The inspector should check the shingles for wear and tear, said Richard Matzen, president of the American Society of Home Inspectors. If water or snow can pool on the roof, for example, you may need a replacement sooner than you think.

Each type of roofing comes with its own wear cycle, Matzen added. Cedar "shake" or shingle roofs, for example, often have a shorter life cycle than other types of roofing, and can be maintenance-intensive if the wood is cheap.

"On my own home, which I bought two years ago, the roof was 30 years old -- a good life span for a shake roof. I knew I could get another six to 10 years before I'd have to replace it, but also knew I'd have to make sure it was properly treated for it to last," said Jim Hastings, a Realtor in Las Vegas, Nev.

The cracked slab You may not know what a "cracked slab" is, but you know it doesn't sound good. Indeed, it isn't: a cracked slab is a crack in the foundation of your home, Knott said. Ignoring a shaky foundation for many years could lead to eventual collapse.

Cracks come from unstable soil beneath the slab, Matzen explained. Soils may be unstable for different reasons: along the Pacific Rim, homes may have seismic problems. In the northern and northeastern states, on the other hand, residents worry about frost and frost heaves, which lift frozen soil like an ice cube in a tray -- and can break a weak foundation in the process.

Repairing a home's foundation would affect resale value, Knott said. Matzen said repairing cracked slabs could cost anywhere from $5,000 to $8,000 for small problems to as much as $50,000 to $60,000.

Moldy walls? Mold itself has been around for thousands of years. But public concern about mold contamination -- and mold claims submitted to home insurers -- have both skyrocketed over the past year, according to the Insurance Information Institute.

Wall mold is common on the West Coast and in desert states like Arizona and Nevada, Hastings said.

"Years ago, we'd see mold in the house from a water leak, in the corner of the shower, and it was no big deal," said Hastings. "But now there are molds that causes health problems -- allergies, or dizzy spells."

Caught early, mold usually can be removed with bleach and water. But if the home is not maintained and the mold becomes hazardous, it must be removed professionally, or "remediated", Hastings said, to avoid health risks. That could cost from $500 to $15,000, depending on its severity.

If your inspector finds any discoloration on your walls, they'll order a mold test, which costs about $300. That will confirm whether you need professional mold removal or not.

Pet odor Rhonda Richardson, a Realtor in northern Virginia, said buyers often underestimate the odor that pets leave in homes, even very clean homes. New owners may have carpets replaced and floorboards bleached to remove odors, particularly from cats, that lived in the home years before you.

"Cats have a tendency to spray and mark their territory. They spray the baseboards and carpet areas," Richardson explained. "If you have any type of allergy or are just very sensitive to pet odor, you may need to think about [the cost of removing those odors]."

Now, any real estate agent worth his salt will have sellers clean their carpets professionally before putting a home up for sale, Richardson added, and that often will temporarily overshadow the smell.

Then they move out and you move in. After some moisture and closed house conditions – say a few days of rain -- the odor could resurface with a vengeance.

Richardson has seen the cost of replacing carpeting and flooring run up to $8,000.

Beware the rot When you buy a home, your inspector will also check how much wear and tear its wood products -- such as outdoor decks and many window structures -- have endured, Matzen said. Decks, for example, deteriorate over time and eventually become unstable and unsound. Replacing one costs between $15,000 and $30,000.

A pressure-treated, well-built wood deck can last some 30 to 35 years. A deck built incorrectly, with a species of wood vulnerable to rot, could be out in five to seven years. Tip: Decks built with second growth forest product -- or young trees -- will be far more vulnerable than decks made with older wood.

Many homes built 10 to 15 years ago have wooden window structures that are vulnerable to rot too, Matzen said. A window replacement project could easily cost between $3,000 and $8,000.

To steer clear of lemons, ask the seller for a CLUE report on the home. (You can't get one unless you're an insurance professional or you own the home, so you'll have to ask the seller for it.) The report will show you every insurance claim filed on the house over the past five years. Reports are available for 90 percent of the insured homes in the United States, Collier said.

"It takes the mystery out of what the buyer is really buying, and out of obtaining insurance," Collier explained. "If you want to insure the home and it has too many claims, you may have a hard time getting insurance at a reasonable price."

Finally, if your certified home inspector does pull up a list of expensive potential properties on that house you "must have", don't be afraid to play hardball.

"If the [inspector] finds structural problems, I would inform the homeowner in writing of the issue and the cost of repairs. The owner can then fix the problem, reduce the expected price, or do nothing," said Kurt Reuss, president of Contractor.com.

If they do nothing, walk away. This is no time to turn lemons into lemonade.