But you shouldn't assume an orphan car will someday become a collector's item, Moody says.

"I could see a Mercury Marauder being worth something to collectors at some point because of its low volume, but I can't see a Mercury Grand Marquis ever being worth much," he says.

So, the expert recommends sticking with orphan cars that offer good discounts over "non-orphan" models -- and suggests focusing on vehicles that are no more than five years old.

"Once five years go by, any discount you'll get will really shrink," Moody says. "The price difference between two similar 10-year-old cars is usually pretty small."

He adds that buying an older orphan model increases the risk that you'll fail to find replacement parts, skilled mechanics or someone who'll fulfill any factory warranty that remains on your vehicle.

Many orphan brands' one-time dealers still offer parts, repairs and used cars to the public years after their new-vehicle supplies have run out, though.

Jason Powell of Canada's Springman's Saab says most dealers who sold the quirky Swedish line before its 2011 demise have "have stuck with Saab even if they've also moved on to selling other brands."

He adds that the automaker's former parts subsidiary remains in business and supplies a worldwide network of official servicers, while an investor has bought Saab's assets out of bankruptcy and hopes to restart operations soon.

Plans call for producing an electric version of the well-regarded Saab 9-3, with possible gas-powered cars to follow.

"Saab is coming back," Powell says. "It's just taking some time to get there."

AM General, which made the Hummer before selling the brand to GM (and which still makes the "Humvee" military vehicle the Hummer was based on), is also planning to soon roll out Hummer kit cars.

That makes Hummer lover Breggin very happy.

"There's something addictive about the Hummer and its combination of technology and innovation," he says. "It's unlike anything else."

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