It all depends on how much experience you have of selling cars, how proficient you are at it, and how confident that your car will sell privately. Agreed, the easy solution is to sell it to the trade, but this is going to hit the pocket hardest. Only you can decide if the hassle of a private sale is worth the extra cash.
If you go the private sale route prepare a carefully scripted but honest advertisement. Choose the best place to advertise it, the Club site or PP, specialist magazine, Autotrader, Pistonheads etc, A badly worded advert always puts me off - if the seller can't be bothered to write an attractive advert, can he be bothered about taking care of his car properly? I know that may not be fair, but it's how it is perceived.
Be honest with yourself about whether what you are selling is just like one of a hundred others, or something a bit special or desirable due to specification or mileage, perhaps. If it is fairly run-of-the-mill, then you are competing purely on price and condition. Remember that the asking prices are not the same as selling prices - deals will inevitably be done.
You can always make the car more attractive to the buyer - you might consider offering to pay for a Porsche 111-point check as a show of confidence in the car, and it will also give the buyer the option of taking out a warranty.
The worst part of selling privately are the no-shows, tyre kickers, and time-wasters. When someone contacts you for a viewing make them aware that you will not allow them to drive the car unless they can show you proof of insurance. This will also give you a good idea how serious they are. Always make sure the car is spotlessly clean for a viewing. Buyers will not look through grime for a jewel underneath. Take them for a reasonable test drive, but drive the car sensibly and sympathetically - they would prefer to buy from an old fuddy-duddy than a boy racer. If you do allow them to drive the car, don't be afraid to tell them to slow down if you don't feel comfortable. And the primary rule is: Never part with a car until the funds are cleared at your bank.
I could write volumes on this, but these are the basics. No, I've never been in the trade, but have bought and sold quite a few cars privately.
A half-way solution might be to get a specialist to sell it on your behalf. Although some of them are happy to do this, and you will get more than selling it to the trade, the specialist will be keener to sell their own stock, in which they have more cash invested.
