Mike O’Dell lives in the Harbour Square co-op along the Southwest Waterfront.

So your dream home happens to be in a co-op building? Don’t panic.

Housing cooperatives, commonly known as co-ops, where residents collectively own their building as opposed to owning an individual unit, may be a bit of a mystery to renters and Realtors, but buying into one isn’t much different from buying a condo.

Washington apartments began converting to co-ops in 1920, and today there are more than 100 market-rate co-ops in the city, ranging from as small as four units to as large as 500, according to the DC Cooperative Housing Coalition. There are also limited equity co-ops, which are usually cheaper, with different ownership rules.

While New York City is the co-op capital of the country, D.C. has one of the highest concentrations of them, with co-ops spread from Dupont to the Southwest Waterfront, plus a few outside the District in Maryland and Virginia.

How Is It Different From a Condo?

The main differences between co-ops and condos are the ownership structure, fees, taxes and application process.

Unlike condos, where you directly buy and own a single unit, in a co-op, residents buy a share in the corporation that owns the building. Some co-ops issue a share of stock and a proprietary lease, while others issue an ownership contract.

Real estate taxes are assessed on the entire cooperative, not individual units, so co-op real estate taxes may be a little lower than condo taxes. Residents pay their share of the real estate tax as part of monthly co-op fees, unlike condo real estate taxes, which are paid separately by the owner.

“The biggest misconception people have [about co-ops] is that the fees are really high,” says Ann Benefield, general manager at The Westchester co-op in upper Northwest D.C. (4000 Cathedral Ave. NW, 202-338-7700). In reality, the increase often reflects the real estate tax, she says. Fees also vary based on services and other amenities that are provided.

Selling your share requires approval from the co-op board of directors, since the new buyer is buying into the whole corporation.

What Are My Options?

Co-ops range from high-rise apartment buildings to garden-style apartments, town houses or even detached houses, and prices are pretty comparable to condos or town homes of similar size and quality.

“An identical co-op and an identical condo probably sell for the same price,” says Mike O’Dell, a director at the DC Cooperative Housing Coalition and an owner at the Harbour Square co-op at the Southwest Waterfront (500 N St. SW, 202-554-3314).

At Harbour Square, a one-bedroom co-op runs about $250,000, while one-bedroom condos in the area range in price from the low to mid-$200,000s.

 Is There a Grueling Application?

When applying for a co-op, buyers need to provide financial information, employment verification, a credit report and letters of personal reference to the co-op board. There’s also usually an interview with the board of directors — a step you won’t face when buying a condo.

While the interview may be a turn-off for some, it’s nothing to worry about, O’Dell says.

“Ours is more of an orientation,” he says. “We talk about … what they should expect, what we expect.”

At The Presidential co-op in Dupont Circle (1026 16th St. NW), the interview is more of a formality, says Scott Osberg, a resident and former secretary of the co-op’s board.

The application and interview can help ensure that the new owners can afford the costs of co-op ownership.

“The only criteria for rejecting a person is financial,” says Theresa Zivanovic, building manager at The Saxony (1801 Clydesdale Place NW, 202-332-8116) in Adams Morgan.

Can I Rent It Out?

Co-ops also often have restrictions on whether you can rent out your unit, and for how long, and the board usually has to approve the request.

Some co-ops limit how long the unit can be rented for ­— say for up to two years — or the total number of units in the co-op that can be rented at the same time.

At Harbour Square, co-ops can’t be rented out for the first two years you live there, and you then can only rent the unit for up to three years, O’Dell says. At The Presidential, only about six of the approximately 40 units are currently rented, Osberg says.

The goal is to keep the units mostly occupied by owners, who have a stronger sense of responsibility to the community.

“The focus of co-ops is really home ownership and personal ownership, not investment,” O’Dell says.

What’s the Vibe Like?

Most co-op buildings offer a range of amenities and events for residents, contributing to a community feel.

Harbour Square residents enjoy such amenities as a club room, library, business center, 24-hour-gym, indoor car wash and a year-round indoor swimming pool that overlooks the Lincoln Memorial reflecting pool.

Of course, co-ops have the same drawbacks as any small, self-governing association, like a condo association. But with a good board and good management, disagreements are easily overcome, O’Dell says.

“Cooperatives are a great way of owning,” O’Dell says. “I don’t know why we don’t have more of them.”