Finding an apartment — let alone an affordable one — has grown increasingly challenging in Colorado and the rest of the nation. With vacancies down and rents up, it’s a landlord’s market.

“I’ve never seen it this bad,” said Cloette Amato, a counselor for the past 17 years at Apartment Finders International in Denver.

Ron Throupe, a professor of real estate at the University of Denver’s Burns School of Real Estate and Construction Management, characterized the market for would-be renters as the worst in at least a decade and predicted that conditions won’t improve “probably for another year or more,” when new units become available.

Carmen Arriaga is among the apartment hunters who have struggled to find a suitable place.

A Denver native, she began searching the local market after earning a master’s degree in architecture at the University of Kansas. On Aug. 1, she moved back with her boyfriend, Colin Weiland, and their dog, and began searching for an apartment three days later.

She’s still looking.

“I have an internship in my field, and I found a part-time job at a Subway within seven days,” she said. “But finding a place to live has been extremely difficult. Apartments are either too small or too expensive, or they don’t take pets.

Arriaga estimates that the couple has visited six apartments and made phone calls on about 12 others. They’ve also driven around in search of “For Rent” signs.

“We went to an open house for one apartment and were only 15 minutes late, and four people had already put in applications for it,” she said.

For now, Arriaga is living with her parents in Westminster.

“The shortage of apartments and the high rent — it’s a double whammy,” she said.

Rachel Dedeyn, looking to move from Minnesota to Denver, estimates she checked out about 20 apartments during a futile one-week search in June.

“It was a lot of looking around and calling and being told there was nothing available,” she said. “Most of the places I visited were not in my price range. It was very frustrating. It took two months, actually, before I found something.”

A report released three weeks ago by the Colorado Division of Housing said the combined vacancy rate for apartments in six metro areas across the state — including Denver, Colorado Springs and Fort Collins/Loveland — was 4.9 percent in the second quarter, down from 5.2 percent in the second quarter of 2011 and the lowest level recorded since 2001.

The vacancy rate was 4.8 in the Denver area, 4.3 in Pueblo and 3.5 in Fort Collins/Loveland.

Meanwhile, the statewide average rent increased 7.4 percent this quarter compared with the second quarter last year, rising from $877 to an all-time high of $942. In the Denver area, rents climbed from $915 to $980 in that time frame.

Numerous factors have contributed to the tight apartment market.

The recession and poor lending environment caused a severe slowdown in apartment construction.

This, at a time when more and more people are clamoring for rental units, whether apartments or homes.

“With people losing homes to foreclosure, they turn to renting,” said Don May, executive director of the Adams County Housing Authority. “Underwriting requirements for mortgage loans have tightened up, so fewer qualify, and those people also are being pushed into the rental market. So what you have is less product for more people.”

The desire for homeownership is also not as strong as it once was, he said.

Renters’ “perspective has changed. They want more flexibility. As a renter, if you get transferred in your job, you’re not tied down to a mortgage, and you don’t have to worry about selling your home. You just give notice to the landlord.”

For many in the business of leasing apartments, these are uncharted waters.

“I’ve never seen this, and I’ve been doing this since the mid-1980s,” said Jim Lorenzen, president of Cornerstone Apartment Services.

“The people who come to us are shopping hard,” he said. “They’re desperate to find an apartment, and there is a lot of frustration”

Lorenzen said his company has about 1,600 units under management and only about 11 that are available for rent.

He said many of his clients are post-college professionals who are attracted to the urban lifestyle. Their average age is 26 to 27. They’re earning about $40,000 a year and are looking to pay anywhere from $700 to $1,000.

“There’s not a lot of availability in the prices they want to pay,” he said.

The problem is particularly acute for those with lower incomes.

Amato of Apartment Finders said rents, on average, are up $100 to $150 a month. On the low end, rents are up $50 to $70 a month.

“I would say 80 percent of my people are struggling,” she said. “They can’t afford many of these places. They’re out of the picture. I just tell them to hold on tight until the economy gets better.”

Given these conditions, those looking for apartments have resorted to different means to get them.

Some go on Craigslist or other websites. Some contact apartment-finder firms. Some attend open houses. But units don’t remain available for long, and in many cases, apartment hunters find that a unit has already been spoken for by the time they get around to looking at it.

Experts encourage would-be renters to go directly to apartment management companies, to drive around and look for “For Rent” signs or to be especially attentive to talk among friends or co-workers who might be considering moving out of a rental.

These days, young urban professionals seem to be attracted to inner-city rentals, even if they are studio-sized, and that tightens those already-tough markets.

The tight conditions have led to a spike in new apartment construction, but that’s small consolation for those with immediate housing needs.

“With the decrease in vacancy rates and the increase in rents, it has caused a boom in multifamily construction,” said Sherman Miller, executive director of the University of Colorado Real Estate Center. “There’s a race to get residential projects out of the ground.

“But it might be 12 months to 18 months before those products come on line.”

Lorenzen said as many as 15,000 new units are expected to become available in the Denver area in the next 12 to 24 months.

In the meantime, however, renters will continue to face difficult odds.

“We’re going to keep looking, but we’re taking a break for a few days,” Arriaga said. “Not being able to find an apartment is driving us insane.”

John Mossman: 303-954-1479, jmossman@denverpost.com