She lived there rent-free, squirreling away her salary. She had no particular goal in mind, other than “to save money and figure out what to do later,” she said. But “with every birthday, I got a little more anxious to live on my own.”

Her favorite class at Brandeis had been international macroeconomics, where she had learned about the housing bubble and the inevitable collapse of prices. So she decided that, instead of wasting her free time on Facebook, she should be checking out apartment listings. Still, she thought of homeownership as something to be entertained in some distant, unspecified future.

But a girl could dream. Maybe, just maybe, there were places priced low enough. ...

It cost nothing to look online. And mortgage rates were just 4 to 5 percent. The figures told her, “now is the time,” said Ms. van Deuren, 27, who is from Rockland County.

She knew nothing about the market. “I was a deer in the headlights,” she said. But she knew she wanted to remain near her grandmother on the Upper West Side, from which she also had an easy commute downtown to her job in advertising.

Her budget range? “Cheap,” she said. That meant in the $300,000s or maybe $400,000s.

It also cost nothing to go to open houses, so she decided to venture out, with the guidance of her parents, “two very practical people who have nothing but my best interests at heart,” she said. “They were my sounding board.”

They started looking last fall, stopping in at an open house at a prewar condominium building on a busy block of West 72nd Street. They arrived to find the fire department there, extinguishing a small fire. But they were allowed to go inside and view some apartments for sale, including a cozy one-bedroom for $450,000.

They were put off by the fire and its flooded aftermath, but they met the listing agent, Sabrina Seidner of Nest Seekers International, and began working with her. Ms. Seidner “gave us a 101 on real estate,” Ms. van Deuren said.

She told Ms. Seidner that she preferred a condo building to a co-op, in case she ever needed to travel and sublet, and hoped for an unattended lobby. “I don’t like people seeing my comings and goings,” she said. “I feel like an idiot if I forget something.”

On that doorman issue, “I kind of went to battle with my parents,” she said. They and others cited security concerns, saying that a doorman building “would hold its value, or something about a good investment being connected with having a doorman,” Ms. van Deuren said. She didn’t buy those arguments, but she and her parents “agreed to disagree and to look at all the options,” she said.

She felt overwhelmed by the hunt. “I would rather be sleeping,” she said, than rushing to appointments. “I hate shopping, because I need to be an educated consumer before I commit to anything, and I am also very indecisive when it comes to making a purchase. Even for $30 shoes, I can’t decide. Am I going to wear them? Or is this going to be another thing that clutters up my closet?”

Studio layouts were often a problem. Ms. van Deuren didn’t want the bed to appear front and center. That was the problem at a 520-square-foot studio on West 93rd Street, listed at $440,000.

But a place on Riverside Drive in the 90s, with an airy, tiled lobby, felt like home. A prewar building, it had an unusual number of studio apartments, Ms. Seidner said. It was converted to condominiums five years ago.

A 400-square-foot studio was in excellent shape. Still, there were few places to position a bed. The one small window overlooked a brick wall. The kitchen was tiny and the closet space limited.