'the green icon replies' are free for the users to view (they just have to sign up)
but I want the users to pay $3 tp view 'the red icon replies'
Do you have any wpforo plugging to do that?
if you don't have any, would you recommend the right plugin go with smoothly with wpforo?
Thank you
do you know what would be the best plugin for it?
I'm sorry but I don't know any which may make the topic paid. You can use some Membership plugin and make certain forum access for payment. But you cannot do that for topics. There is no topic specific accesses. wpForo has only Forum Specific accesses. And the forum accesses are related to all topics under that forum not to a certain topic.
Here is some good topic how to use aid membership plugin to make some forum accesses paid: https://wpforo.com/community/how-to-and-troubleshooting-2/wpforo-and-restrict-content-pro/#post-21412