Robert Stolank for The New York Times

kate Harvey, left, and Rebecca Kotler Wein, lived in an office with seven roommates.

LIKE the legions of aspiring poets, tap dancers and musicians who came before her, Nina Rubin, a 29-year-old graduate of Wesleyan University, has struggled to find halfway decent housing in New York. Earlier this year, she ended up in her most unusual home yet: an office.

After taking a job as an instructor at Outward Bound, Ms. Rubin, along with some of her co-workers, settled into the top floor of the organization’s Long Island City headquarters. She camped out in a bunk bed; others converted nearby office cubicles into sleeping spaces, or pitched tents on the building’s roof. To create some privacy, they hung towels and sheets around their bunks.

While Outward Bound officials stress that they view these cubicles and tents as temporary housing solutions, Ms. Rubin, who has since moved to Vermont for a short while, was grateful for a free place.

As the apartment-hunting season begins, fueled by college graduates and other new arrivals, real estate brokers say radical solutions among young, well-educated newcomers to the city are becoming more common, because New York’s rental market is the tightest it has been in seven years. High-paid bankers and corporate lawyers snap up the few available apartments, often leading more modestly paid professionals and students to resort to desperate measures to find homes.

While young people in New York have always sought roommates to make life more affordable, they are now crowding so tightly into doorman buildings in prime neighborhoods like the Upper East Side that they may violate city codes.

They are doing so in part because the vacancy rate for Manhattan rentals is now estimated at 3.7 percent, according to data collected by Property and Portfolio Research, an independent real estate research and advisory firm in Boston. It is expected to shrink to 3.3 percent by the end of this year and to 2.9 percent by 2011.

“It’s only going to get more difficult to rent an apartment in New York City,” said Andy Joynt, a real estate economist with the research firm.

“While rents continue to rise, it’s not sending people out of the city. There’s still enough of a cachet,” he said. While New York City has always had a vacancy rate lower than most other cities, rental prices jumped last year by a record 8.3 percent. Some potential buyers, scared by the national slowdown in housing sales, decided to rent instead of buy. The housing crunch has also been exacerbated by the steady growth of newcomers.

The relocation division of the brokerage company Prudential Douglas Elliman had found homes for 4,000 families moving to the New York, New Jersey and Connecticut area in 2006, a 15 percent jump from the year before, and many of them wanted to live in Manhattan. Stephen Kotler, executive vice president of the division, said he expected business to increase by 15 percent again this year, based on the requests he has already received from banks, consumer-products companies and media firms. Even though his clients can afford high rents, he said, they do not have many choices.

“There’s going to be limited inventory and a lot of demand,” Mr. Kotler said. “There just hasn’t been enough rental product built,” he said, as, developers have said that the price of land and the costs of construction in the last few years have made it impractical to build rental buildings. They have instead focused on condominiums.

Renters without high salaries have not been shut out of the market. They are squeezing in extra roommates or making alterations as never before much to the frustration of landlords. The rents for one-bedroom apartments in Manhattan average $2,567 a month, and two-bedrooms average $3,854 a month, according to data from Citi Habitats, a large rental brokerage company, but rents tend to be far higher in coveted neighborhoods like the Upper West Side and TriBeCa.

Because landlords typically require renters to earn 40 times their monthly rent in annual income, renters of those average apartments would need to earn at least $102,680, individually or combined, to qualify for a one-bedroom and $154,160 to afford a two-bedroom.

Young people making a fraction of those salaries are doubling up in small spaces and creating housing code violations, said Jamie Heiberger-Jacobsen, a real estate lawyer with her own practice. She is representing landlords in 26 cases that claim overcrowding or illegal alterations in elevator buildings in Murray Hill, the Upper East and Upper West Sides and the Lower East Side. A year ago, she handled a half-dozen such cases.

Ms. Heiberger-Jacobsen said she was seeing the overcrowding not only in tenement-type buildings, but also in doorman buildings. “It really does create fire hazards,” she said. “You can’t just have beds all over the place.”

But more renters are finding that they cannot afford to stay in the city without resorting to less conventional living arrangements. For the last five years, Mindy Abovitz, 27, a drummer and graphic designer, has been living with four roommates in a 1,500-square-foot loft with one bathroom in Williamsburg, Brooklyn, which has become a haven for young people, that rents for $2,600 a month.

Her rent is a bargain, she said, because comparable spaces now cost as much as $4,500 a month. To accommodate everyone, the roommates created five bedrooms out of three by building walls from drywall and lumber. Then they soundproofed the walls with carpet padding to limit the noise.

Dividing the space has been an affordable solution, Ms. Abovitz said, though the loft becomes crowded when she and her roommates get ready for work or prepare meals. “The kitchen and the bathroom are where you find the most traffic,” she said. Students on tight budgets find it especially tough to find housing. Last fall, Kate Harvey, a part-time nanny and a junior at N.Y.U., and eight friends saved on rent by camping out in vacant offices at Michael Stapleton Associates, a downtown explosive-detection security firm. For nearly three months, they told the guards at 47 West Street that they were interns, even as they trudged in near midnight or pattered through the lobby at 10 a.m. in pajamas and slippers.

Ms. Harvey’s father, George Harvey, who is the chief executive of Michael Stapleton Associates, had lent them the space, which included two kitchens and two baths, after his company moved into a new office before the lease on its old one expired.

They sneaked furniture into the 11th floor on the freight elevator, squeezed three beds into the former chief executive’s office and turned filing cabinets into clothing drawers. One student pitched a tent. They brought their cat, Sula, past the front desk. They knew pets were allowed, they said, because the company had allowed bomb-sniffing dogs. While most of the students who were interviewed said that they came from families that were fairly comfortable financially, they said that area rents were so high that they could not afford both housing and tuition.

“It was nine girls and a cat,” Ms. Harvey said, sipping on steamed milk in a Greenwich Village coffeehouse. “At least three of the nine would have had a really hard time paying for school and staying there.”

Mr. Harvey said his daughter told him that some friends had spent the summer sleeping on friends’ couches and even in the N.Y.U. library because they could not afford rent. “They were in some tough financial situations,” Mr. Harvey said. “It occurred to me that all this space was going to waste.”

Now Ms. Harvey and two roommates from the office are looking for a new place to live. Each can spend up to $800 a month. Ms. Harvey has been searching the Craigslist Web site for apartments, but so far she has had no luck. She says she is hopeful that they will eventually find something in Brooklyn, perhaps in the outer reaches of Park Slope.

“We’re definitely going to have to expand our definition of Park Slope,” she said.

Copyright 2007 The New York Times Company. Reprinted from The New York Times, New York Report, of Thursday, May 10, 2007.