If you are in the process of looking for a new car and have already got one that you need to get rid of then you have three main options. If the car is old, has a lot of problems or is not in a resalable condition then you may decide to scrap it. You can often get the best deal for scrapping your car by ringing local car scrappage companies and finding out how much they would offer you for it. You can often haggle slightly on this although some will have a set price which they will pay. The heavier the car is the more likely you are to get for it.
If you are buying a new car from a garage then you may be able to trade it in against that one. They will often not give you as much for a car that is part exchanged than you would get if you sold it privately but this is a great way to eliminate the hassle and time taken to sell a car privately. Again you can haggle n this price and try and get a bit more for your car. You should always take a car in to be valued when it is clean and tidy and be sure to check that oil levels etc are topped up.
The final option is to sell the car privately. This is the way to often get the best price for the vehicle but you may have to contend with a lot of time wasters before the car goes and will have to advertise it yourself.