Buying a home is a process that is full of pitfalls. Something that seems relatively minor can prove to be quite costly in the future, so it pays to have a list of “red flags” that you can mentally check off to help to protect your investment.

To that effect, we’ve compiled a checklist of seven red flags to watch out for when buying a home. Pay careful attention to the items listed here—each and every one is a potential deal breaker and may have a serious impact on your bottom line. Let’s take a look at what you need to watch for.

Foundation Cracks

Hairline cracks in foundations are commonplace, but anything over ½ inch warrants a professional inspection. Your foundation is key to the overall structural integrity of the house and large cracks may be indicative of an enormous problem, with the first consideration being safety —making this the top entry on the list.

Beyond safety considerations, repairing a foundation down the line can be very costly and this could even make your home ineligible for refinancing, so if the cracks are over ½ this is a huge warning flag that you don’t want to ignore. 

Strange Smells

Strange smells in a house are often indicative of mold and while most mold isn’t always of the toxic variety, these smells tell you some very important things about the house. First and foremost, where there is mold, there is moisture.

According to Fox Family HVAC, an air conditioning repair and replacement contractor, “This means that water is leaking into the house somewhere and so this is something that you will have to add to your costs if you want to protect your investment. Realistically this will mean finding and sealing the leak, but it may also require replacing plumbing fixtures and wood, so that minor smell you’ve noticed could be a costly red flag.”

Humid Air

When you are inspecting a home that you are considering, pay close attention in warm areas. There is a difference between hot and humid, and that difference is moisture. If you notice that a warm area has a certain amount of humidity associated with it, pay attention to the building materials used in this area.

The current build should be sufficient to withstand the existing moisture. If not, then you face the possibility that there might be damage to the home that isn’t yet visible and at the very least, remodeling costs to remediate the issue before it becomes a problem.

Water Stains

Water stains are a big warning flag and should never be ignored. If you notice them in a home, look carefully to see if they look a bit brown or yellowish. If so, there might be a plumbing problem that will need to be fixed along with any damaged materials. Furthermore, this could also mean that you’ll have mold and mold spores in this part of the property and this is a health consideration that should not be ignored.

Bottom line, if you see water stains then you’ll need to have the damage professionally assessed. Fixing mold issues can cost a lot of money if left unattended for too long. 

Fresh Paint

It’s not uncommon for a prospective home buyer to be greeted with a freshly painted house, but take careful note if that new paint is only visible in certain areas. Brand-new paint that is only visible in one or two rooms is a potential red flag, as someone might be trying to cover up stains or other deficiencies indicative of damage that devalues the home. If you see it, be sure to ask about it, and tell your home inspector to pay special attention to these areas—failing to do so could be a costly mistake.

Antiquated HVAC System

Legacy HVAC systems, at the very best, should be viewed as a definite cost modifier. The average AC system has a working lifespan of approximately 10 to 12 years, while a furnace is rated for a more robust 15 to 18 years. Older systems are also going to cost more to run, as efficiency naturally degrades over time. Finally, older systems might come with leaky ductwork and are definitely not worth the risk.

If the home has an older furnace or AC then this is a notable red flag, and you may need ​​air conditioning repair and replacement. At the very least you’ll have more expensive bills and at the worst, they’ll go out during the summer or winter and require a potentially expensive replacement. 

Old Shingles

The roof of a home must be carefully inspected to ensure that shingles are flush and solid. Look for curling and cracking in the shingles and keep an eye out for exposed nails. Replacing a roof isn’t cheap, with current estimates ranging between $350 to as much as $600 per every 100 square feet.

You’ll also want to check out the areas beneath such damage as well, just to ensure that the roof integrity has not been compromised to the point that the interior has become damaged as well. Old shingles are a huge red flag, so if you see them then further investigation is definitely warranted before proceeding with a buy.