Before selling, any of your good cars makes sure that the title of the car is available, and then visit a mechanic to check for it any problems and get it cleaned to impress any potential buyers. Remember that you are doing this to get big money for any cars that are still in good working condition. If you are looking to get money for cars you are selling you need only to assure that said the car has a title and you need an assessment value to ensure that you are getting the maximum value for cars you are selling.
The next step is to find a potential buyer in the car market who pays good money for any vehicle that are still good and advertising in print or online is the best way to do it. Seasons have an effect on said market so it's easy to find people who will pay for cars that are in demand during the said season. Any potential buyers will pay good money for cars that are family sedans for any basic inexpensive during the spring break or summer holidays. It is a slow time to sell cars during fall and winter is hard, but if you do know of someone who is willing to pay cash for cars you're selling during said seasons let them know that you have what they need.
There is also a market for people who pay cash for the cars that are classified as collector cars like a 1966 Ford Mustang GT and a 1940 Ford Custom. Such cars take some time before being sold because said buyer will want to evaluate the price of the car first. However, with the right buyer expect goodly sum of cash for the cars that you are buyer has taken a fancy.
Now you are thinking of getting cash for the cars that you have around. Let the buyer know what body parts and systems don't work anymore and you must also let the buyer know which parts are missing. Try getting your junk cars repaired; you can expect a buyer to pay more cash for junk cars that are working and road worthy.
If you are junk cars, seem to be unsalvageable, try checking it again. You might be surprised to know that you can get some cash for derelict cars that have parts that are salvageable and can be sold individually. While it seems to be a good idea to get cash for junk cars that are whole, in some cases it is better to sell each car part individually. To save some money try delivering junk cars yourself instead of getting it towed, salvage yards that have towing services will be billing you for such services and you can also get more money for junk cars that they will not have to drag.