Uh, thanks for posting twice.
OK, I won't be a smart ass anymore.
I had a guy from the east coast call on my '87 Targa I have for sale. He said he would be in town over the Thanksgiving holiday and would like to come by and take a look at the car.
He came, saw, and drove the car (sorry about the leaks!) and then returned home saying he had another car to look at near where he lived.
He ended up passing on my car because of the shipping cost but he did call and thank me for taking the time to show the car. I in turn thanked him for coming to look at it. Truly a Thanksgiving exchange! Or a Thank-fest. Whatever. The point is that he was nice enough to call back even though he found another car to buy.
Most people don't bother.
If I go look at someones car, I call later and thank them for their time...even if we're passing on the car.