If you’re shopping for a New York City apartment, you’ll quickly discover that many co-op buildings are prewar, and most pre-wars on the market are co-ops. That being said, even though we all love the character of these old structures –– think hardwood floors, tall ceilings, and large spaces brimming with character and charm –– not all prewar homes are created equal.
You’ll need to be on your toes during the search, so look out for these six red flags when shopping for a prewar co-op.

Cracks in the walls

Beware of cracks, especially if they’re horizontal. Vertical cracks are usually bothersome but less serious. Large horizontal cracks could mean structural issues and might be worth looking into. Cracks typically worsen over time if not repaired, so know that the apartment will require some work from the get-go. What’s more, just because a crack is repaired doesn’t mean it won’t return.

A trashy or dirty basement

If you’re considering making an offer, be sure that you thoroughly inspect the basement. Filled garbage bags, stray items, dirt, and a generally grungy appearance probably mean that the building isn’t all that well maintained.
When my husband and I were shopping for a co-op about six years ago, I recall a great apartment that we passed on because the basement reminded me of a horror film. We ended up buying in a building that was spotless, instead.

Strange odors

I’m not sure what it is about odors in New York City apartments in general, but 18th and 19th-century brownstones and tenements (walk-ups) have thinner walls than grandiose prewar high-rise buildings, so you’re more likely to catch every whiff of smoke or aroma of Chinese takeout. Be on the lookout for anything attempting to mask said smells, such as home fragrances or candles. And know that if you choose an apartment above a restaurant, odors are pretty much guaranteed.

If a sponsor rather than the shareholders own more than half the shares in a building, the sponsor will have control over decisions on issues like maintenance increases, repairs, and general operation. You’ll also have a tough time securing financing in a building in which the sponsor has more than 50 percent control. So unless you’re an all-cash buyer, you probably want to run from this.

Sagging doorways and sloping floors

Structural issues aren’t uncommon in townhouses, especially. Looks at headers (the tops of doorways), and take notice if they’re sagging, or out of square.  In a similar vein, do you recognize any slope in the floors? At this point, you might want to hire an engineer to inspect the home, so you know what you’re getting into before even making an offer.


Fairly common in prewar buildings, assessments are typically in place for capital improvements. Most often, these charges are added to your monthly maintenance bill. Ask questions about the project and improvements, and how long the extra charges will be assessed. Also ask if there are any forthcoming improvement projects you should know about, which would only increase your monthly expenses.


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