Are you paying too much for that new car?

Cars are already expensive enough, with the average new car costing more than $30,000. So the last thing you want to discover is that you paid thousands of dollars too much. But some car buyers are finding that is the case.

The reason: Some dealers’ are selling new vehicles at significantly more than the sticker price, often in violation of the law, says Daniel Blinn, a consumer law attorney based in Rocky Hill, Conn. (Sticker price refers to the manufacturer’s suggested retail price, or MSRP, that appears on the so-called Monroney sticker affixed to the vehicle window.)

Blinn says elderly people and uneducated consumers are at particular risk of being tricked into paying more.

There a few excuses for this practice. Under the federal Truth in Lending Act, dealers cannot charge you a higher vehicle price because of a low credit rating (although you can be charged a higher interest rate on the car loan).

And in California, the law bars dealers from selling new cars above MSRP unless they provide a supplementary window sticker that conspicuously displays certain information, including the MSRP, a statement that the selling price is not the MSRP, and a list of any items not included in the manufacturer’s price.

Yet Connecticut courts have found dealers guilty of committing an unfair trade practice when they sold new cars for above the manufacturers suggested retail price without attaching a so-called supplementary sticker to the vehicle outlining the additional charges.

Blinn says leasing is a particular problem because people don’t fully understand how it works.  He’s seen some lease payments based on vehicle prices that are as high as $10,000 above MSRP.

He warns car buyers not to be tricked into paying more than sticker by dealerships claiming that a vehicle is in high demand. Rarely is that the case, he says.

Another way you could end up paying more is if you agree to add a lot extras that may be unnecessary, such as service contracts, credit life insurance, rust-proofing and undercoating, and fabric protection. Some dealers have been caught adding extras into car purchase agreements without customer consent. That was among the allegations in a recent $1.8 million settlement the New Jersey Department of Consumer Affairs reached with eight dealerships in that state.

For more advice, read our new car buying guide.

What to do

Find out what it should cost. There are many resources for determing what a fair price should be for any vehicle. Among them is Consumer Reports New Car Price Service and the free TrueCar.com. Other options include Edmunds.com and KBB.com. But don’t just stop there. (See the next item.)

Negotiate. Remember that many cars sell for well below sticker and even so-called invoice, the amount the dealer supposedly paid the manufacturer. The only way to truly know the best available price is to contact at least several dealers. You can do so by phone or electronically, through the dealers’ websites. Let the dealers know that you’re a serious buyer and that you’re shopping for the best bottom-line price. Negotiate the price of lease vehicles just like you would if you’re buying.

Wait out the market. If you can't get a below-sticker price from any dealership because a car truly is in heavy demand and short supply, rest assured, production will catch up with demand and negotiation room will emerge. Let the market cool for a couple of months, and you may find it easier to get a good deal.

Don’t concentrate on monthly payment. Dealers like to focus your attention on the monthly payment instead of the vehicle price. With low monthly payment associated with leases and long-term loans, it’s easy for them to disguise the fact that you’re paying too much.

Read the contract. It may be tedious, but you never know what the dealer may have slipped in. Verify that the vehicle price matches the one you negotiated, including for a lease. Also make sure that you got full credit for any vehicle you traded in (negotiate that amount, too). Question any charge that wasn’t on the manufacturer’s window sticker. Check carefully for extra dealer fees or add-ons you didn’t authorize.

—Anthony Giorgianni

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