WATERLOO - The four-stall garage is so full of antiques and various collections there is no room for the cars. They sit outside.

So is David Sondrol's life as an admitted and committed pack rat. It's not that he's messy. He just finds value in many things others might not.

"I'm not one to go out and save paper bags and Styrofoam containers. What I save is something of worth or value," Sondrol says.

Sondrol saves a variety of things. As an antique dealer, he's always acquiring more vintage items. He also saves glassware, coins, pottery, pencils, pens, photographs, coin banks, toys, postcards, souvenir china and wooden thermometers.

When he was young, he wrote to celebrities asking for photographs and autographs. He saved all their responses in the original envelopes. He has more than 500 that fill several boxes. His favorites are from John Wayne and Alfred Hitchcock.

Other prized collections include a retrospective of advertising from Oelwein businesses and old calendar plates, some as old as the early 1900s.

Sondrol is one of many Americans whose possessions dominate their living spaces. Some, like Sondrol, have life under control. But compulsive hoarding can become a dangerous pastime. What starts as clutter could evolve into a fire hazard, obsession or haven for dust and mold.

"The question I would ask is, 'What impact is this having in his or her life?'" says Seth Brown, a psychology professor at the University of Northern Iowa. "If it's just filling up a basement, that's fine. If it's causing problems, fights with family, safety or bio hazards, then this is a problem."

Psychologists who study obsessive-compulsive disorder are just beginning to investigate hoarding, behavior that often mirrors OCD habits, says Fugen Neziroglu, author of "Overcoming Compulsive Hoarding: Why You Save and How You Can Stop."

Neziroglu is the clinical director at the Bio-Behavioral Institute in Great Neck, N.Y. In a phone interview, she said she's identified three main types of savers through her research.

- Instrumental savers are those who save because they're afraid they'll need it in the future and won't have it.

- Esthetic value savers are those who save items which they think are unique and beautiful.

- Sentimental savers are those who attach a sentimental value to all their possessions and can't bear to part with any of their memories.

"For them, the possession is almost alive, it's an extension of themselves," Neziroglu says. "If they discard an item, it's a loss of themselves. … The possessions have life to them."

So it is for Beth Adams, whose Waterloo home is filled with trinkets and collectibles, all of which have a story. Those rocks on top of the television? From her grandchildren.

The embroidered miniature houses? Three for a dollar at Goodwill!

"Got it at a rummage sale" is Adams' favorite punch line

"You never know when you might need something," says Adams, a self-described "rummage-sale freak."

Numerous boxes, trunks and plastic containers in Adams' basement are filled with so much stuff she has forgotten what's in each one. Someday, though, she'll find a use for the dozens of old floppy disks, wallpaper scraps and green plastic berry containers.

Eventually, some of Adams' treasures are turned into something creative and useful. She had her friends save laundry detergent bottles, which she somehow made into turkey centerpieces for her church's Thanksgiving dinner.

Some people, like Gary Wilcox, are more instrumental savers. Wilcox, administrator for the Black Hawk County Solid Waste Management Commission, saves all papers and documents that have ever crossed his desk. He calls it a "file by pile system." He has not seen the top of his desk for more than six months.

At Wilcox's last job, his supervisor warned him that if his borderline fire hazard of a desk wasn't cleaned up, he'd be fired.

"He didn't fire me. And not long after that saved stuff that saved his butt," Wilcox says. "Us pack rats, the attitude is, 'I hate to throw it away because as quick as I do I'm going to need it.'"

Away from the office, Wilcox collects Diecast cars, which fill nearly 30 boxes and sit in the hallway of his house.

Neziroglu says hoarders most commonly save newspapers, magazines, junk mail and plastic bags. She's also seen unusual collections, like an entire basement full of vases or the person who taped so many television shows that VHS tapes lined the perimeter of every room in the home.

Neither Sondrol nor Wilcox has run out of room yet. Sondrol has a backup plan for excess. Anything that doesn't fit in his Oelwein home or garage goes into his rented storage unit.

Stacey Palevsky can be contacted at (319) 291-1580 or stacey.palevsky@wcfcourier.com.