[crazyhorse]

If you'd like to see a well moderated "classified ad" section on a forum, please look at the classified section of www.fordpinto.com . This is a well run forum, and quite well moderated, if I do say so myself
Most importantly look at the feedback section. 90% of it is positive. Yeah there are a few bad apples, but those are everywhere. Most members, even when posting negative feedback, use tact & finesse, to get thier points across. Even when literally thousands of dollars are involved.
The "PG13" rating is always preserved, mostly by the members themselves. It may be that the average ages of the members there is higher, but there's only ever the RARE event of flaming. They even have a Demo Derby section, dedicated to the destruction of thier beloved Pintos. To the best of my knowledge no-one has ever been banned there. Not saying that it's not neccessary from time to time though.
I compare these 2 forums because they both are very well run, and well moderated. They both also cater to a very narrow spectrum of the automotive scene.