Sellin a car = bullshit

There is no ettiquette. Business is business. I've been on both sides of this fence and I'm sure I'ma dick to many sellers and buyers as a result. I was just involved in buying my step-son's first car. Limited cash, etc etc etc. I pissed off several people. but we got a decent car at a fair price (and a Dodge to boot!).
If you need money - sell the car and solve your problem. If you can make do without selling it, don't. But don't ***** about guys telling you what it's worth to them because your numbers differ. Just tell them no. I personally called them names...lol. I've also shut the garage door on one guy's feet.
Honestly - no joy rides or "hear it run" (when selling engines) until an offer is made and the ride/run is to validate the description and verify condition.