Harley Quinn's apartment is the residence of the DC Comics character, Harley Quinn. This particular location relates to the version of the character featured in the "New 52" continuity.
Harley Quinn's apartment is a low-rent multi-storied apartment complex located in the Coney Island district of Brooklyn in New York City. The bottom of the complex is perimetered by a barb wire fence, and Harley lives in an upper room. Other tenants who live in the same complex as she include Madame Macabre, Big Tony and the Amazing Goatboy. Harley lives in her apartment with her pet Dachshund named Queenie, and a talking beaver named Bernie.
When Harley first moved into the apartment, she got it in her head that she wanted to do away with all possible "pests", which meant she wanted to rid herself of competitors who stood in the way of her particular lifestyle. She began sleepwalking and in her subconscious state, she put a hit out on herself. Two members of the Brooklyn Assassin's Guild named Jerry and Karen answered the call. They burst into Harley's apartment and tried killing her. Harley was still sleepwalking at the time, but her friend Poison Ivy was present to defend her until she woke up. Upon doing so, she killed Jerry by throwing a knife into his throat, and then killed Karen by throwing her out the window onto the barb wire fence, which sliced her in half. (Harley Quinn Vol 2 7)