The home inspection is that pivotal event you hold your breath for when buying a house. It’s an opportunity for a licensed expert to scrutinize every inch of your potential new place for minor and deal-killing problems.

But when so much is on the line, why wait until the inspection to start investigating? Open houses and private showings are the perfect time to get a little nosy. Let us be clear: I'm not suggesting you should forgo the expertise of a home inspector. But you can get a jump-start so that you can turn your inspector’s attention to some potential problem areas.

These eight crucial problems can be easily uncovered—even without a home inspector’s license. So go ahead and take a peek.

1. Cracking caulking

Get on your knees and examine the caulking around the sinks and tubs. While cracking could be a sign of age, it also might indicate mold inside the wall (a no-go unless you’re up for a major challenge).

“Any cracks or holes must be taken care of before you go further,” says Bill Horne, a former landlord and commercial real estate owner. Keep an eye out for dark stains, which also might indicate something nasty growing underneath.

2. Insulated recessed lighting

You may not get to peek in the attic during a showing, but do your best to scamper up there. Access to the attic means checking insulation issues, storage space, and safety problems—like poorly installed recessed lighting.

Once you’re up there, find out where the recessed lights are installed. Is there insulation resting on the cans?

“It’s a fire hazard if there is,” Horne says. “You’ll have to be sure the lights are replaced or the insulation repositioned if so.”

3. Insulation with foil side up

While you’re poking around the attic, take a peek between your feet. If the home’s insulation has been installed between the joists, you’d better not see your reflection.

“If the insulation’s foil side is up, it will probably have been ruined by moisture coming up,” says Horne. Also called the “vapor barrier,” the foil-lined side should face the warm side of the house—i.e., your main rooms—not the cold attic.

To be clear, if you look up and see foil, that’s OK. Insulation installed between the roof rafters will have the foil facing down, protecting the (relatively) warmer attic from the chilly outdoors.

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4. Slouching walls

It’s not just a two-episode gag from “How I Met Your Mother.” Crooked or leaning walls or floors that aren’t level can indicate serious foundation issues.

There is no need to bring a level to every open house. A careful eye is good enough (until the inspection, that is). And here are a couple of fun hacks: Set a coin on its edge. If it rolls, you’ve got a crooked floor. Or press your cheek against the wall and look for strange slopes or irregularities.

You don’t need to dismiss a home simply because it’s crooked. Remember: Old structures settle in curious ways. But if what you see seems peculiar, add it to the must-inspect list.

5. Rusty basement columns

If you get to poke around an unfinished basement, Horne recommends examining the lally columns—the skinny steel tubes that hold up the main beams.

Look for peeling or rust, which “is a sign that there might be dampness in the cellar,” he says. Even if moisture tests don’t indicate a problem, rust could compromise the column's support.

6. Multiple pipe styles

Mixing multiple pipe styles doesn’t necessarily mean something nefarious is afoot. Perhaps the homeowner was replacing the system piecemeal and ran out of cash (hence the sale?). But if you see a mix of several styles—maybe some are cast iron and some PVC—you’ll want to alert your inspector to find out why. Frozen water pipes might have forced a partial replacement.

Poor winterization and the resulting burst pipes don’t necessarily mean anything is bad.

But “it’s a danger sign, because it means that there was a lot of water in the cellar at some point,” Horne says.

If the sellers handled the problem, the home should be safe to buy. If they didn’t, it’s your problem now. And water issues create a nightmare headache.

7. Slow drainage

During a walk-through, let the water flow—everywhere the Realtor® will let you, at least. Turn on the faucets for every sink, toilet, or tub, and watch carefully as the water drains.

“Slow drainage indicates clogged drains or substandard installation,” Horne says. It gets worse: You could even have a sewer line disaster waiting to happen—and that’s an expensive fix.

Horne also suggests visiting the cellar or basement while everything is draining. Look for drips—another good way to identify potential plumbing or pipe problems.

8. Too few vent pipes

While checking out the backyard, peek at the roof and count the vent pipes. One vent pipe should line up with the kitchen, and an additional vent pipe should be for each bathroom.

Like most issues, a shortage of vents doesn’t make the home uninhabitable. Sure, if the bathrooms aren’t vented, it might mean an additional expense, but it’s not the end of the world.

But don’t assume you’re in the clear, even if the kitchen and all bathrooms are vented. If the vent ends in the attic, it could send dangerous amounts of moisture into your home.

Make sure to draw your home inspector’s attention to the problem and let your Realtor hash it out with the seller. Your smart detective work could lead to a better deal on your dream home or keep you from buying a money pit.