Save $500 to $5,000 on a new car with a $10 tool

In Sunday's Your Money column I write about the methods I used to help a friend get a good deal on a new Subaru. No I didn't buy him a new car for the holidays, but people supposedly give new cars as Christmas gifts. December ranks as the top month for U.S. car sales, with about 1 in 10 vehicles sold in December, according to Bloomberg.

And those king sized bows? A Los Angeles company called "King Sized Bows" appropriately enough, said that it sells about 2,500 car toppers each year, with buyers split evenly between consumers and dealerships. So far, I haven't been able to find the king sized bows distributor in Minnesota.

Let's say that you are one of the lucky ones purchasing a new car soon. One important negotiating tool if you're buying a new vehicle for yourself or a loved one is to find out if there are secret dealer incentive programs. Sometimes known as dealer "holdback," these programs are in addition to special low financing rates or manufacturer rebates.

These incentives can be significant--starting at $500 and going as high as $5,500. That is why it is often possible to buy a vehicle far under the invoice price, said Robert Ellis of Checkbook.org, a non-profit that includes car buying services. Incentives may increase because a car isn't selling well, dealers are overstocked, or a newer model is coming out soon and the manufacturer wants the old models off the lot.

You can find out which vehicle models currently have dealer incentives at several sources. If you order the Consumer Reports New Car Price Report for $14, it indicates if the model offers dealer incentives, holdbacks or rebates. But if you want to see a list of all vehicles and their holdback amounts, go to CarDeals. For $10 you can get a list that can be printed. The current issue is dated Dec. 19, but the Dec. 9 issue included these secret incentives:

$1,000: BMW 3-series 2015 (excluding 328d)

$2,000 to $2,500: Chevy Cruz 2014, Hyundai Elantra Sport 2014, Mercedes C300 Sport Sedan 2015 4matic, Toyota Prius Liftback 2014 (excludes Prius V, Plug-In and C)

$4,000 to $5,500: BMW 7-Series 2015 (excludes Alpina), Chrysler 300C 2014 (excludes 300/SRT/300S) and Ford Taurus 2014

This is only a sampling. Many more incentives are listed in the issue. The holdback incentive is not a guarantee that the dealership will pass along the savings to the customer, but it's a powerful tool to take into negotiating.

This is why the buying technique mentioned in the Your Money column is so helpful. Let the dealers bid against each other via email or by phone. The one who can afford to sell you the car for the lowest price will rise to the top.

Not every vehicle will have an added incentive. My friend's Subaru only had low interest financing offer--no holdback, but I was still able to get the vehicle for $250 under invoice.