• Rent control means there’s a maximum base rent (MBR) set on a case-by-case basis by the New York State Division of Housing and Community Renewal (DHCR). A landlord can raise rent by up to 7.5 percent yearly until the MBR limit is reached.

• Rent-controlled apartments are only in buildings built before February 1, 1947, and you (or your family) must have occupied the space continuously since before July 1, 1971.

• A place is stabilized if it’s in a building with six or more units built pre-1974. The Rent Guidelines Board issues a percentage of allowed rent increase every year.

• Currently, landlords are allowed to raise stabilized rent by 3 percent for one-year contracts and 5.75 percent for two-year contracts.

• If a new tenant moves into a rent-stabilized apartment, the landlord can raise the rent 17 to 20 percent.

• When stabilized rent reaches $2,000 per month, it becomes destabilized—but only if the annual household income is more than $175,000 for two years prior.

• A few coveted buildings have J-51 or 421a status, which keeps them stabilized no matter the rent. Go to home2.nyc.gov/html/dof/html/property/property_tax_reduc_j_51.shtml.

• Presently, 59 percent of Manhattan apartments are rent-stabilized, and 42 percent of Brooklyn’s; the Bronx, 57 percent; Queens, 43 percent; and Staten Island, 15 percent.

• For a list of rent-stabilized buildings, go to housingnyc.com and click on “Apartment Guide.”

• If a landlord renovates a stabilized apartment, he’s entitled to raise rent by one fortieth of the construction costs. Painting and plastering don’t count—it’s all about overhaul.

• Before committing to renting or buying, check out how many violations the building has on record. Enter the address at nyc.gov/hpd and get a peek at the last 20 years or so.

• Housing code violations are classified A through C. Those in categories B and C are considered hazardous, while A classifications are of a less-dangerous nature.

• Your sketchy-housing alarm bells should sound if you see recent violations relating to lead or asbestos.

• Wanna know what previous tenants paid? The DHCR has rent histories for stabilized apartments from 1984. Bring photo ID and proof that you’re a tenant to 25 Beaver Street.

• If the previous tenant was paying significantly less, you can file a rent overcharge complaint—and potentially restabilize your rent if it was unlawfully raised over $2,000.

• If your agent calls himself a Realtor, he’s a member of the National Association of Realtors and must adhere to a strict code of ethics.

• NYC law requires all buildings to supply heat between Oct 1 and May 31 when the outdoor temperature falls below 55˚ during the day and 40˚ at night.

• Real-estate brokers and agents are licensed by the New York Department of State. Brokers can work independently; agents work under brokers.

• When you purchase a condo, you own your place from the walls inwards. A co-op tenant doesn’t buy the actual apartment, but owns shares in a corporation (the property).

• Generally, condo buyers must put down 10 percent of the purchase price. Co-ops usually look for at least 20 percent in cash.

• Condos tend to be pricier per square foot than co-ops: Citi Habitats reports that in 2007 the average NYC co-op studio was $393,000; the average condo studio was $558,000.

• Condo owners pay monthly real-estate taxes and communal charges for upkeep.

• Co-op maintenance fees vary (they depend on whether the building has a doorman and a mortgage), but they hover between $1.25 and $1.70 per square foot. Taxes are included.

• Per Citi Habitats, average rent for a studio in a doorman building in Manhattan is $2,206. Forgo the doorman and save 21 percent (and a year’s worth of B.S. conversation).

• There’s a world beyond Craigslist. Search Rent Direct New York (rdny.com) or NY Bits (nybits.com) for no-fee apartments. RDNY even notes which ones are rent-stabilized.

• Co-op prices increased by about 3 percent between 2006 and 2007: In ’06 the average was $892 per square foot; in ’07 it hit $918. Meanwhile, condo prices leapt nearly 9 percent, shooting from $1,123 per square foot in ’06 to $1,222 in ’07.

• As of the most recent Housing and Vacancy Survey in 2005, two thirds of New York City residents are renters. (Nationally, it’s about one third.)

• In 2007, the rental-vacancy rate in Manhattan was .97 percent. This is compared with a national average of about 9.7 percent.

• In the first quarter of 2008, overall average Manhattan rent prices decreased slightly from the same quarter in 2007.

—Kate Lowenstein

Sources: Sam Himmelstein and Kevin McConnell of Himmelstein McConnell Gribben Donoghue & Joseph, Christopher Dente and Itzsakun Garay of Citi Habitats, Gino Pozzobon of Apple Mortgage Corp, nyc.gov, housingnyc.com, rdny.com, nybits.com, Citi Habitats Residential Market Report, and Black and White Report