Person Handing Key to Another Person (© Rubberball/Mike Kemp/Getty Images)

Like fall, spring is a traditional new-car season. But before most people can buy a shiny vehicle just off the production line, they must first sell the outmoded one sitting in their driveway. And that can be easier said than done. Not everyone is familiar with the subtleties of selling a car, truck or SUV. If you're not careful, it can be little more than an opportunity to lose an awful lot of money. Even seasoned pros make costly mistakes. Here are 10 things not to do if you want to get the most money from what you're selling, no matter the car or the circumstances.

Bing: Selling Your Car

1. Don’t trade it in at the dealer.

No matter how friendly the salesperson or how much money you spend, one thing is for sure: The dealer will never give you what your used car is worth. Commercial resale margins for used cars are notoriously thin, and it's always in the dealer's best interest to lowball you, even if it decreases the chances of a sale. You'll almost always get more on the open market. The only exception is if you're fabulously wealthy and don't mind giving up thousands of dollars for the sake of convenience.

Read:  MSN Autos Top Value Picks

2. Don’t show a dirty car.

It may sound obvious, but a clean car is easier to sell than a dirty one. The logic is simple: People like buying new things, and few people want someone else's lived-in, worn-out garbage. We're not just talking a simple wash and wax here, either. Go for the works: paint cleaning and polishing, interior shampooing, the works. If you do it yourself, it's free — that is, pure profit — and if you pay someone, it's rarely more than $100. Either way, presenting a clean car makes it easier to convince people that your vehicle is worth what you claim it is.

Read:  Keeping Up Appearances

3. Don’t waste money on repairs prior to sale.

This one is a personal choice. Some people sell their cars with a laundry list of needs, while others fix everything under the sun before moving on. The key, however, is moderation. No one wants to buy a car and immediately send it to the mechanic, but you shouldn't go overboard. Err on the side of safety and driver enjoyment, but don't spend money on things few people will notice, like early filter replacements or unnecessary fluid flushes. When in doubt, ask your mechanic.

Read:  Mechanic Mishaps

4. Don’t list your car in a vague or illogical manner.

The old saw holds that the three most important words in real estate are location, location, location. In car sales, it's advertising, advertising, advertising. Take time composing your ad. Avoid listing in little-read places like your local newspaper's classified ads. If you're selling a special-interest model, seek out enthusiast forums, whether in print or on the Internet, and run picture-heavy listings. Build an online photo gallery and include the link with every ad. The key is remembering that somewhere out there, someone desperately wants your car. You may just have to work to find that buyer.

MSN Autos: Used Car Research Tools

5. Don’t use bad photos.

These days, most private used-car sales take place on the Internet. The Internet is a visual medium, so it makes sense to cater to people's curiosity: Photograph your car thoroughly, and shoot more pictures than you think you need. If you don't have the camera skills to make your car look good, ask a friend who does. The goal here is to answer a potential buyer's questions before he sees the car in person, and to eliminate wasting everyone's time.

Bing Images: Used Cars

6. Don’t sell at the wrong time.

For most people, a car purchase isn't taken lightly. You'd think the month you sell your car wouldn't be that important, but it is. Don't sell a car in winter, when people aren't inclined to stand outside to look at it. Don't sell at the beginning or end of the month, when bills are due and most people don't have ready cash, and avoid tax season for the same reason. And if you're selling an emotionally charged vehicle like a high-powered roadster, avoid scheduling test drives during bad weather; gloomy days make fun cars seem like an extravagance.

Read:  The Incentives Have It

7. Don’t offer untrustworthy proof of condition.

Knowledge is power, and when it comes to used cars, the more you know, the more powerful you feel. Few things lure a buyer like a pre-purchase inspection from a reputable source. Pre-purchase inspections are relatively cheap — usually $70-$120 at your local auto dealer — and give both you and the buyer a third-party verification of your car's condition. You also increase the chance that the car will be bought on the spot, which decreases the amount of time someone will spend thinking about whether your asking price is worth it.

Bing: Car Buying Horror Stories

8. Don’t be unprepared to show it.

Let's paint a picture: Joe Carbuyer shows up at your house, license in hand, ready to test drive your car. The car is in the garage, buried under bicycles and assorted lawn equipment. The kids are running around the driveway screaming. The records are somewhere inside, but you can't find them, so you have Joe sit at your kitchen table while you scramble around for half an hour. Would you buy a car in that environment? We think not. Preparedness and forethought go a long way.

Read:  Car Buyer's Checklist

9. Don’t put too much or too little stock in “blue book” values.

Comforting though they may be, published estimates of used-car values, such as the Kelley Blue Book, are just that: estimates. Because they're based on high-volume, often sight-unseen auction sales, such numbers aren't always accurate. If the car is in any way special — a low-production model, for example — its estimated value could be low by as much as several thousand dollars. By the same token, if your car is a worn-out rat, even the lowest published number isn't going to be correct. Your car is worth what someone pays on the day of sale — no more, no less.

Link: Kelley Blue Book

10. Don’t hold back the sale because you don't like the potential buyer.

Don't laugh; it's a common mistake. Many people assume that they have to like the person they're selling their car to, especially if they have an emotional attachment to the vehicle in question. It's not true. You're peddling a machine, not auditioning for a soul mate. A difficult person may make negotiations unpleasant, but at the end of the day, cash is all that matters. If someone has interest and money, move that metal. If not, move on. It's as simple as that.

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Sam Smith is a journalist, a Southerner, and a reformed Alfa Romeo mechanic who spends most of his time mooning over leaky old motorcycles and small-batch bourbon. A multiple International Automotive Media award-winner, he has covered cars for Automobile Magazine, Car and Driver, and Esquire, among other publications. He once drove 4,000 miles in a weekend for a hamburger and has only been threatened by the German police twice.