Skip the restaurants, too. Lamoureux says he and his girlfriend avoid restaurants as much as possible, as well as pricier grocery stores. "We buy our produce almost exclusively from what is essentially a seconds market, where prices are at a significant markdown but with reduced shelf life."
[Read: 5 Smart Ways to Save on Groceries.]
Don't live large. Lamoureux and his girlfriend lack an air-conditioner – when you're paying $165 a month on student loans, you tend to want to scale back – and they went without a TV for awhile, too, but have since splurged, paying $72 a month for cable.
"Very little furniture in our place for the moment," Lamoureux says. "We're embracing minimalism in the home."
Look for the free stuff. Most cities have experiences and events that don't cost much, says Jean Towell, manager for TheMintGrad.org, a website aimed at helping millennials and recent graduates with their finances.
"Many museums and cultural attractions offer free or discounted admissions on certain days of the week," Towell says, and she adds that especially during the warmer months, many cities have a full schedule of "free or very cheap concerts, performances and fairs."
Of course, anyone in the suburbs or countryside might start wondering why people live in the city. No air-conditioning? Spending a fortune on what feels like a few square feet? No meals or drinks out?
But there is an undeniable energy that many cities have, as well as numerous career opportunities, and of course, everyone's financial situation is different. Some people have to live lean to survive and grow their bank accounts; others can partake more in what cities have to offer.
Hupp says she and her boyfriend aim to pack lunches every day instead of shelling out more than $10 for lunch, because saving that money frees them up to do the expensive outings that crop up later. Living in the big city, like anywhere, is all about choices, and Hupp and Cain – who are already working on building their savings accounts, retirement funds and IRAs – are trying to make good ones.
"Many people don't understand why we don't want to go out for drinks every night of the week," Hupp says, "but as cliché as it is, we say, 'We are living like others are not today, so that we can live like they are not, later.'"