An expert has revealed the best ways to haggle down the price of a car.

1. Know what the hell you really want.

Too often in my car business days, some “smart” car buyer would negotiate hard on a car in our inventory until we could finally arrive on a price. Then, they’d come in and drive it just prior to finishing up the paperwork. Guess what? About half of them would test drive and get cold feet, saying “Uh…I’ve got some thinking to do.” Then they’d buy another car.

The point: Don’t negotiate on a car until you’re sure you want it and you’ve driven the car (or one very similar). Otherwise, you’re spinning your wheels.

2. Use the phone.

The tendency is for people to try and negotiate the best deal over the Internet, but at most dealerships (sadly) the phone is still the best way to get the right person involved.

Who’s the right person? The New Car Manager. Call and ask for him or her, then tell them you’re looking to do a deal as quickly and easily as possible, and that you want to work out most of the details over the phone. If the New Car Manager isn’t too busy, he or she will work with you. If they are too busy (or too arrogant), call back towards the end of the business day…Tuesday and Wednesday nights can be a great time to work out a car deal with a manager over the phone.

3. Call lots of dealers.

Call lots of dealers when you’re hunting for the best price.

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4. Kick your trade.

Trade-ins screw up deals for a lot of reasons. If you can, sell your trade-in yourself.

If you can’t, approach your trade as a separate transaction. Call dealers, ask for the used car manager, and them ask them what they’ll buy your car for (with no trade). This is called a “buy bid.” While some dealers will low-ball you, others will offer you market. After you do this a few times, you’ll have a very good idea about what it’s worth. You can then insert the trade at the very last step, confident that you’ll get something close to the best buy bid. If you don’t, you can take the car to the dealer with the winning bid (only the threat of taking the trade will probably get you the money you’re looking for).

NOTE: Buy bids are usually hard to get over the phone, but you can usually find out when you can drop by for a quick bid. In the here and now, dealers are pretty aggressive about buying cars off the street. It’s a great way to get a fair market appraisal.

5. Don’t worry about all the dealer’s business details.

Like how much holdback they’re getting, or what the advertising fee really means, etc. Car buyers often out-smart themselves by trying to understand all the nuance in dealer pricing. Don’t waste your time – just ask for the best “out the door” price and leave it at that. Let the dealer worry about how they’re making a profit – it’s their problem, not yours.

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6. Use Edmunds and TrueCar for guidance, not gospel.

Both tell you what you can expect to pay for any given vehicle, and their numbers are usually pretty good. However, they’re not gospel – if the words “the Internet said…” fall out of your mouth, you’re making a fundamental mistake: What the Internet says isn’t reality. If Edmunds says you should be able to pay less than every dealer is quoting, Edmunds is likely wrong.

7. Keep it friendly and polite.

As a new car manager for a lot of years, I’d get calls asking for quick and easy deals and good prices. If the person was nice to me, I had no problem with shortcutting the entire process. Not only was it a nice way to spend my time (wayyy better than talking to my salespeople), but it was also a great way to reward my most efficient salespeople by giving them a deal I’d negotiated.

However, if the caller treated me like I was some sort of sub-human slime (and a lot of them did), guess what? I wasn’t willing to work with them over the phone. Call it foolish (I could have made more money by taking some abuse), but I expect to be treated like a decent person. Most of the people in the car business feel the same way.

Jason Lancaster is the editor of AccurateAutoAdvice.com

This post originally appeared on Quora and has been republished here with full permission.