If you've never looked for a rental in New York City, it will probably come as a shock to learn that many apartments are represented by real estate agents who charge you (not the landlord) a hefty fee if you wind up renting. Expect to pay a broker's fee of anywhere from one month's rent for a less-than-prime apartment or location, or for an apartment that's lagging on the market for some reason, all the way up to 15% of a year's rent (that's $5,400 on a $3,000-per-month apartment).  

A "no-fee" apartment, on the other hand, is one that you rent directly from the landlord or management company, or one for which the broker's fee is being paid by the landlord (usually because the apartment is undesirable for some reason, or because the building is new and the landlord wants to fill it in a hurry).   

There are plenty of situations where it makes sense to use a broker--such as when you've exhausted your options for finding a no-fee apartment.  Read on for the lowdown on both avenues.