So you’ve decided to buy a new or pre-owned car. You know the make, model and year of the chariot. You even know what features you want. Now it’s time to head to your local dealer and sign on the bottom line, right? Not by a long shot. It’s now time to negotiate price. If you want to get the most bang for your buck, here are 10 phrases you should never utter in earshot of a car dealer — and why.

“I’m trying to keep my monthly payments down.”

Click to enlarge pictureWoman Buying a Car (© Radius Images/Jupiterimages)

Know the maximum you are willing to spend over the life of your loan before you start to negotiate.

Families think in terms of their monthly budgets, but most experts agree that’s not the way to price out a car. “Don’t be bamboozled by some superficially attractive monthly payment,” says Joe Ridout, spokesperson for Consumer Action, a nonprofit advocacy group. “There are a lot of ways for a dealer to make monthly payments appear low.” Before you walk into the dealer, know the maximum you are willing to spend over the life of your loan. By stretching the term by a year or two, a dealership can easily bring a $400 monthly payment down to a $300 payment, but you could end up paying thousands more in interest.

“Honey, what do you think?”

Click to enlarge pictureMan and Woman Car Shopping (© Image Source/age fotostock)

Put up a unified front by knowing what you want before visiting a dealer. Otherwise, you can lose your negotiating position.

Dealers love indecisive couples. By subtly playing a husband and wife against each other (“Seems your wife’s really interested in the luxury package; she’s obviously got good taste.”), buyers are routinely talked into things they might not have otherwise considered.  “Never show emotion,” says Robert Sinclair Jr. of the American Automobile Association of New York. “If one of you gets all excited or emotionally attached to a vehicle, then you lose your negotiating position.” Couples buying a vehicle should have a very good idea of what model vehicle they want, what options they are interested in and how much they are willing to spend before they walk into the dealership. If unforeseen issues pop up that merit further discussion, don’t be afraid to ask the dealer to give you some time alone for discussion before making a decision — better yet, sleep on it — then come back as a unified force.

“I have a car to trade in; how does that affect the deal?”

Click to enlarge pictureCar buyers and sales associate (© Juice Images/age fotostock)

Get the right price on the car you’re buying before even mentioning the possibility of a trade-in, and know the market value of both.

Don’t discuss a trade-in until you’ve settled on a price for the car you’re buying. Making one deal contingent upon the other just allows the dealer more flexibility in his negotiations. Do your research on the value of both vehicles and get the right price on the car you’re buying before you even mention the possibility of a trade-in. The truth is, you’ll almost always get a better price if you sell your old vehicle yourself. A dealer trade-in is a convenience, but he’s not doing you any favors. Make sure you do your research on the true price of your desired vehicle as well as the value of your trade-in (MSN Autos has tools for determining both) before you arrive at the dealership, and be prepared to sell your old car somewhere else if the dealer doesn’t offer a fair price.

“Let’s talk financing!”

Click to enlarge pictureCar Keys and Loan Application (© Comstock/Jupiterimages)

Don’t let the rate of a loan influence the price of the car, and don’t be afraid to shop around. Dealers rarely offer the best terms.

Again, settle on the price of the vehicle you’re interested in before you bring up financing — don’t let the rate of a loan influence the price of the car. These days, loans may be harder to come by, but Consumer Action’s Ridout suggests that credit unions still offer the lowest rates. “Show up at the dealer with an offer ready to go,” he says, “then see if the dealer will beat it.” If the dealer is offering special low financing rates as an incentive from the manufacturer, see if you can turn that into cash back on the car instead. Then go shop around for the lowest rate from a third party. Also, keep in mind that advertised rates are usually for the shortest possible term (usually 36 months). If you stretch out the terms, the price can go up steeply — make sure you calculate the total cost of the loan and make sure there is no early payment penalty.

“Here’s how much I have to spend.”

Click to enlarge pictureWoman Shopping For a New Car (© VStock/age fotostock)

Don’t just blurt out how much you want to spend. Discuss the car and the options, then let the dealer make the first offer.

Avoid tipping your hand right when you walk in the door. You have no idea how much the salesperson is willing to deal, but if you blurt out your target price, you can be sure that he’s not going to offer you anything lower than that. Discuss the car and the options you’re interested in and let the dealer make the first offer — these days, inventories are so large that dealers will sometimes sell at invoice just to get cars off the lot. Right now, it’s a definite buyer’s market.