Generation Y is one generation that keeps you guessing.

From the years that define it (demographers are still arguing about which dates should be used) to the racial compositions (the most diverse in history) to the conflicting personality (entitled but altruistic), this is a group of Americans whose overriding characteristic is its resistance to being defined.

But apartment executives must do their best.

“It is incredibly important that you market to Generation Y,” says Al Neely, the Washington, D.C.-based chief development officer for Archstone-Smith. “I always tell myself, ‘It's the lifestyle, stupid.'”

Take Natalie Asaro, 21, who works part time while attending San Diego State University. She picked her current residence based solely on its location. She found her apartment online and opted to rent in the expensive Pacific Beach area that is closer to the ocean than her classes or her job.

“I just had to live by the beach,” Asaro says. “It's not the cheapest place, but there is a lot going on down there, so it's worth it.”

MEET GENERATION Y: Natalie Asaro, 21, wants to live in your property—but only if it meets her requirements. She says she doesn't mind sharing the two-bedroom townhouse with three friends because she likes the idea of being within walking distance of not only the beach but also the party atmosphere of Pacific Beach. She lives about 15 minutes away from the other big party scene in San Diego, the downtown district called the Gaslamp Quarter. (Her drive to school takes her about 20 minutes without traffic, she says.)

When she graduates next year and has a full-time job, Asaro says she wants to find a place with the same social proximity but with other upgrades.

“We have friends who have all of the amenities like granite countertops and stainless steel appliances,'' she says. “We don't even have an icemaker right now. But as soon as we can afford it, we want those things.”

To capture the attention of renters or buyers like Asaro, there are three musts that multifamily decision-makers should remember: technology, amenities, and design.