So is the cost of CO Gun Market just a membership in RMGO or do you have to be a member AND pay more?

I see nothing wrong with requiring RMGO membership to sell on an RMGO site ... I do think if it were free there would be more traffic, but since they require people to put emails or phone numbers in ads you don't have to be a member to browse and buy, just sell.

I am a little disappointed that RMGO bought the Colorado CCW forum and shut it down.