It remains to be seen if President Obama’s $787 billion stimulus bill, with $17.4 billion allocated for automakers, could be the shot in the arm they need to restore flagging sales–which were down 36.6% in the U.S. in January.

Unfortunately, today’s popular, downsized, fuel-efficient vehicles that promise dependability and affordability over the long-term are not the cars that translate to profits for the automakers. Instead it’s the higher-priced, less-practical vehicles that make more money; they also continue to cost consumers long after they’ve driven off the lot.

“People need to be looking at all these various costs, such as depreciation and insurance and maintenance and repairs and fuel efficiency,” says David Wurster, who leads product development and industry analysis for Vincentric, an auto-industry data analysis firm based in Bloomfield Hills, Mich. “Those always should be areas to be considering when you’re purchasing a car because they separate a good buy from a money vacuum.”

To wit: Most buyers will do just fine with the $98,500 Mercedes-Benz SL550 Roadster as opposed to its $190,700 Mercedes-Benz SL65 AMG Roadster counterpart. The AMG costs so much more because of its ultra-specialized, ultra-powerful engine, which guzzles more gas. Never mind that the AMG has some of the highest depreciation, insurance and maintenance costs of any car on the road.

To find the costliest vehicles to own, we used data from Vincentric to calculate the costs of depreciation; interest on the loan; fuel; maintenance and repairs; taxes and fees; and insurance over five years, then divided the results into 11 segments (excluding low-production vehicles from the likes of Aston Martin and Bugatti) to find the most expensive models in each class.

What we found is common sense: Cars with high sticker prices tend to cost the most over the long haul. German automaker Mercedes-Benz, in particular, dominated our list, with five segment winners, including the $194,950 S65 AMG sedan and $88,500 E63 AMG wagon.

But exceptions do occur. At $53,460, the Chevrolet Suburban is priced less than the $55,340 Lincoln Navigator SUV but has a higher ownership cost due to its higher depreciation rates and poor fuel economy.

Another pertinent finding sometimes overlooked by consumers: The cost of ownership far outweighs the initial price. Prospective buyers would do well to remember that the $58,400 Infiniti FX50 will have an actual cost of $85,152 after five years of paying for gas and maintenance to keep the vehicle running well.

James Clark, the general manager of Automotive Lease Guide, an auto analysis and forecasting firm based in Santa Barbara, Calif., says consumers are delaying the purchase of new vehicles and canceling altogether plans to buy less-than-practical vehicles like the cars on our list.

“The coupe, the convertible, vehicles like that, that are really more of a second or third car, have really struggled,” Clark says. “At this point, it’s a ‘nice-to-have.’ It’s not a need. I think this environment is just kind of pushing people toward something more practical than those types of vehicles.”

While depreciation is far and away the greatest cost in the first five years of ownership, fuel costs are significant as well. But some cars demand proportionately more fuel than others.

The Chrysler 300 SRT8, with its gas-guzzling HEMI V8 engine (owners must pay a gas-guzzler tax on its 13-mpg city mileage), will require roughly $11,979 to fuel for five years. That’s hundreds of dollars more than the fuel required for many similar sedans and coupes.

Hybrid vehicles in particular can pose a false dilemma when it comes to fuel. The Cadillac Escalade Hybrid, for example, uses thousands of dollars’ worth of gas per year.

“The time to recoup that cost through fuel-economy savings alone is longer than most people keep their vehicles,” says Jason Fogelman, a Los Angeles-based auto writer who maintains the About.com guide to SUVs. “In most of the SUVs, the hybrid system doesn’t really have that great of fuel efficiency. It’s … not really Prius-levels of fuel economy.”

The base model of the conventional Escalade ($63,155) gets a combined 15 mpg, while the hybrid version (base price: $74,085) gets 20 mpg. At a rate of 15,000 miles driven per year and assuming the current national average cost of gas ($1.93/gallon), it would take Escalade owners almost eight years to recoup the premium they pay for the hybrid version.

Maintenance is another major factor impacting ownership costs. Buyers should always research how much mechanical attention a particular model needs before they close a deal.

If the maintenance interval is “5,000 miles, you’re going to have a lot more maintenance opportunities than you would if it was 7,500 miles,” Wurster says. “The fewer times you’re in the shop having maintenance or changing oil, the better off you are.”

Of course, most people who buy ultra-luxury vehicles can afford to spend more on maintenance as well as on gas. For them, the thrill–not to mention prestige–of owning such a high-value car trounces any qualms about the expense.

As the economy sours, however, justifications for such an expenditure tend to dwindle.

“Luxury vehicles in general have suffered some pretty significant declines in the past year as people have adjusted their spending,” Clark says. “Now that the market has sort of shifted in the other direction, it’s a challenge because they’re so expensive compared to where it used to be.”

SOURCE: FORBES

David Wurster could hardly believe it recently when he filled the tank of his Ford Focus ZX5 with gas that cost just over $1.60 a gallon. It was a far cry from the $3.60 he paid last summer. But Wurster’s not letting himself get used to the new low.

“It was great,” says Wurster, who leads product development and industry analysis for the auto consulting firm Vincentric, in Bloomfield Hills, Mich. “I think in the short term it’s going to go down more, in fact. But this is the short term. Don’t get comfortable. We’re going to see $3 again.”

It’s the unease of impending high gas prices and the shaky economy that necessitates consumers arming themselves with as much information as they can before heading out to buy a new car, experts say. And the research can pay off, since the true costs of owning a car are realized only after you drive off the lot, not when you hand over a cashier’s check for the car itself.

In Depth: Most Affordable 2009 Vehicles

Take, for example, the $22,990 Volkswagen GTI and the $23,565 Jeep Wrangler Unlimited. Though comparable in price, the two-door GTI’s fuel efficiency (21 mpg in the city and 31 mpg on the highway) and low maintenance costs help make it the most affordable compact premium model.

The Wrangler Unlimited SUV, however, fares worse when it comes to affordability over five years. Its lower gas mileage (15 mpg in the city, 20 mpg on the highway) and the higher cost of insuring a mid-size SUV make it more expensive to drive than a smaller car of comparable sticker price.

Dan Jarvis, a Ford spokesman, says more drivers, especially young ones, are making the “very wise” decision to do this kind of research online before talking to a dealer.

“They are looking at the overall cost over the life of the vehicle,” he says. “And the millennials, as we call them, are also doing the research for their mothers and fathers. So they know about insurance costs and maintenance and fuel costs. They’re looking for that value.”

Behind The Numbers
To identify 2009’s most affordable vehicle in each major market segment, we used Vincentric data to add to the base price the five-year totals for fuel costs, maintenance and repairs, as well as the average national insurance rates in each segment. To find the gas expense, we assumed an annual rate of 15,000 miles driven per vehicle at a price of $3.25 per gallon (the 2008 year-to-date average). We then evaluated affordability based on the percentage of each vehicle’s five-year costs compared with its grand total costs, including base price.

Experts say the key to choosing a truly affordable vehicle is to know what your needs are–and stick to them. Nowhere is this more important than when considering buying an SUV. The Kia Sportage, for example, is the most affordable SUV overall on our list. The base model costs only $16,695, but still offers luxury-associated amenities such as keyless entry, alloy wheels and full power accessories. But it leaves out the heft, which helps keep its gas costs low, getting a combined 22 mpg.

Most SUV owners don’t really need the extra towing capacity of a larger, heavier SUV for making weekend trips to Wal-Mart, says Jason Fogelson, a Los Angeles-based auto writer who maintains the About.com guide to SUVs. Consumers should buy the smallest, most fuel-efficient vehicle they can get away with, he says–the Kia fits the bill for those who truly need an SUV. And despite recent generous deals on full-sized SUVs, buyers should remember that they’ll usually save more money on their initial purchase and on gas later on if they choose the smaller SUV or engine.

“Plan for expensive gas, and plan for fuel economy,” Fogelson says. “And take a second look at that V8 and make sure you really need it before you buy it. You’re going to pay for it in the very near future in my opinion.”

Scaled-Down Luxury, Bigger Savings
Of course, smaller vehicles tend to cost less to own over the years than crossovers and SUVs. The Nissan Versa, which topped the compact entry-level segment, costs roughly $26,000 to own over five years, while the Chrysler 300, the large premium sedan winner, costs almost twice that much. But opting for the smaller car doesn’t mean settling for chintzy workmanship and a bare interior.

The compact-car market consists in large part of buyers under the age of 35–most of who want wireless connectivity, good fuel economy and a decent sound system, all at an affordable price, Ford’s Jarvis says. In short, they appreciate–demand, in fact–luxuries in their small, fuel-sippers.

“People want small, they want fuel economy, but they want the creature comforts they see in other cars,” Jarvis says. “They want the leather seats. They want heated seats. They want [the voice-activated communication system] Sync.”

Nissan’s $9,990 Versa option packages include amenities like fog lights, a power moon roof, Bluetooth capability, leather-clad detailing and premium speakers–all luxury components previously unheard of in compact, entry-level cars.

The Bottom Line
So what really matters when searching for an affordable vehicle? Keep in mind smaller, cheaper cars tend to include less equipment, which reduces weight and improves fuel efficiency. They also tend to have lower maintenance fees.

But if a small car doesn’t suit your lifestyle, do your homework on long-term costs, since certain segments, like luxury sedans, are crowded and all the cars are not made alike.

Models like the Volkswagen Tiguan SUV and Ford Fusion mid-size, for example, are both in crowded segments, but each is the most affordable in their class because they have lower fuel costs and lower long-term maintenance costs than their competitors.

Consumers should also shop around for insurance, getting multiple quotes on several different vehicles. Most insurance providers use their own formulas to determine how to price their coverage, so the cost is a variable that can fluctuate even within a given region.

Jarvis took all that into account before he bought his 2009 Ford Focus, which cost him $14,995.

“If I’m on the highway cruising along at 60 miles an hour, I’m getting 42 miles a gallon,” he says. “It’s amazing. And that was with my wife in the car and with a whole bunch of groceries!”

Consumers who do their homework, as Jarvis and Wurster did, will feel much less of a pinch should gas prices spike again in the summer ahead.

SOURCE: Hannah Elliot@Forbes.Com