As an ex-New car salesmanager, hopefully I can add a few tips.
1.) Never trade your car in. A big no no as you can save yourself $5000 on average most of the time quite a bit more. Dealers do want and need your car, as they make more on used cars than new, so if you can't sell it you can always trade, but please use that as a last resort. Yours would probably take under a week, as late model BMWs are very desirable.
2.) Be nice, you know honey catches more flies than vinegar!!
3.) Bring competition into the equation. Definately shop around!! Albeit the internet or local dealers(if you have more than 1). Tell the Porsche dealer in the nicest way possible that you have a better offer but would like to give him the opportunity to earn your business.
The nicer you are the farther you'll get. We always hated the Jackasses and made every attempt to knock them down a few pegs.
By all means try to sell your car outright. You have a BMW, not a 'K" car or ford focus. It is a desirable car. Easiest way to sell a car outright.
1.) Establish a price. You know what you were willing to "give" It to the dealer for, so that is your lowest price, now do some searches on the net and in your local papers, to see what the highest is. The amount in between is your comfort zone.
2.) Find the Closest, biggest cities newspaper. Mine would be Columbus Ohio. You get the biggest bang for the buck in your ADV Dollar that way. Ebay Sucks for sellers and there are too many dealers in the trader magazines.
3.) Don't ever give away your home adress or phone number. After talking with them, meet them in a very public place, preferably a bank parking lot or near the a police station. (just being cautiously smart).
Good luck, and please don't take this as preaching. I have been in the car bus for more than a decade and just would like to share my experience with a fellow (potential) Porsche owner
