Perhaps after the F/S ,F/A or F/T designation could be a : Scanner or Amateur tab that could be selected. You would then ignore what does not interest you.
A clearly,carefully worded post title may help as well.
When you are in the market for something,(if you are like me you are motivated to check the classifieds "multi" times) you get familiar with what is on "page 1" very quickly.
If it's on page two or later, it's generally sold.
Half the fun is hunting for a bargain

I say no to compartmentizing in sub forums.