How to handle classifieds

[DlandryTSI]

Currently we have a variety of forums on our site and recently we have had issues with users abusing our classifieds section. What I mean by this is once they hit there 50 technical post limit they are upgraded to premium status which gives them access to the classifieds section. Once they have access they spend maybe 80% of their post count posting items for sale or wanting to buy something.

My question is if you run a classifieds section on your forum how are you preventing "power sellers" from posting or controlling the limit? We are looking at doing something on our site and are open to ideas.

Thanks,

--Dave