Pity the poor penthouse at 14 East 4th Street, also known as the Silk Building. The 4,400-square-foot, four-floor unit was once owned by pop star Britney Spears, but since she sold the place a decade ago, it's been on a real-estate roller-coaster. (You might even say that something about the place appears to be…toxic.) (Sorry.) Spears sold it in 2006 for $4 million, and in the years since, various brokers have tried moving it for various prices in the range of $5 to $7 million. It reappeared on the market in 2015 for a whopping $9 million, was de-listed in October, and is now back for $7.6 million. (h/t 6sqft) It's a nice enough apartment, with three bedrooms (including what appears to be a full-floor bedroom with a "dressing area") and outdoor space, but considering its history, we wouldn't be surprised if another chop is in the cards.