I completely agree, Bob.
I've mentioned the same thing to several of my friends and not one of them had anything bad to say about it.
I say make them all classified ads, and even a small one should cost something. Of course, bigger ones, or ones that last for longer times would cost more. There could be an advanced selling type of membership that included the smaller type ads for no charge.
There should be zero communication about the sale in the forums. All communications should be between the seller and the buyer. All financial transactions should be either required or at least recommended to go through a current internet payment service such as paypal. I'm sure AZ could find a way to remove themselves from liability. If all they do is sell ad space, then the only thing they are liable for is providing the space and the associated fees.
Or, you could just do away with it all together.
Royce Bunnell