If it’s time to buy a new car, one of your most important jobs will be getting the most money you can for your old car. If you know how to get the best trade in value for your car, the larger your down payment will be, and the lower your car loan and monthly payment will be.

You owe it to yourself to do everything that you can to get the best price for it. Here are ways that will help you do that.

Clean it up—like REALLY clean it up

A car has a higher value just for being clean! But if you’re going to trade it in, you’ll want it to be as close to showroom clean as you can get.

That will mean a good wash and wax. If you aren’t really into washing and waxing your car, you should have it done professionally. Better still is having it detailed, as in detailed cleaning. When you have it detailed they’ll not only wash and wax the car, but they’ll carefully clean the lights and mirrors on the exterior, and also vacuum and shampoo the upholstery and carpets on the inside, as well as thoroughly clean the dashboard and every inch of the vehicle.

It can cost anywhere from $30 to $100 and up to have this done, but it will be some of the best money you’ll ever spend.

Tune it up

A tune up can make a big difference as well. The car can run and sound better just as a result of changing the spark plugs, flushing out the fluids, and replacing any worn or cracked hoses. And not only will the engine run and sound better, but when the buyer or the buyers mechanic looks under the hood, the engine will look better, and better maintained.

This will also be a good time to take care of any cosmetic flaws. Replace any light bulbs that may have burned out and repair any minor dings or dents. This can usually be done inexpensively with low cost repair kits available at auto parts dealers.

If the wheel covers are badly worn, or if one or more are missing, it will be less expensive to get inexpensive generic replacements at a box retailer. You can buy four covers for about $25. They won’t be the originals of course, but they’ll be shiny and new and uniform.

Know the value before you sell or trade in the car

One of the reasons people don’t get the best trade in value on their cars is because the dealer has superior knowledge about car values. You can level the playing field by knowing exactly what your car is worth before you attempt to trade it in.

You can do this easily by going to the right websites. Edmunds.com is one such site that can give an excellent appraisal of your car’s value. Be sure to put in as much relevant information as possible, and be honest about the car’s condition—all are factors. When you have the value, be sure to print off a couple of copies—one for you and one for the dealer.

There’s no guarantee that the dealer will give you what the website appraisal indicates the value to be, but you’ll have bargaining leverage going in. And if the offer the dealer gives is too low based on the website appraisal, you’ll know that it’s time to leave the store and find another dealer.

Sell it yourself

If the offer the dealer makes is unsatisfactory, or if you think they may be playing games (giving you more for the trade in, but raising the price of the car you’re buying) you always have the option to sell the car yourself. By selling it yourself, you have a much better chance to get the true value of the car.

There are inexpensive ways to sell a car, including placing large for sale signs in the car itself, placing flyers at work, in church, at shopping centers, and by word of mouth. Beyond that, you can list if for free on Craigslist, and consider some other online sales outlets, such as Autotrader.com.

Selling a car is all about gaining exposure, and the more places you advertise it, the greater your chance of selling it at the best price.

If all else fails, there’s Carmax

Carmax will buy your car even if you don’t buy a car from them, and they have more than 100 locations (and growing). You can usually get a better price from Carmax than you can get on a dealer trade in, and you also have the advantage that Carmax will pay you in cash. You’ll know exactly what you have for your down payment, rather than relying on fuzzy estimates from a dealer.

If you do sell your car to Carmax, be sure that the car is in good condition and isn’t more than seven or eight years old. Carmax only buys what they can sell, and a 15 year old beater won’t be one of them.