Pay for submit / Limit of Events

Hello, first – so sorry for my bad english!! I hope the community understand my posting. I have the feeling that I am so close to the solution that I have been looking for a long long time. However, I am missing one of the (for me) most important settings. I would like to offer my visitors the opportunity to submit and publish events – BUT, they should not be able to do this for free. I have now found a way that I can unlock it via user roles by assigning the customer who has paid the appropriate role so that he can post events. But, can I set somewhere that he can only submit one event? So a predefined event limit? EventPrime is really great! I would immediately buy the Premium++++ version, but I urgently need the possibility that the event creator can only create one event or, even better, has to pay something per event. I would be very happy if you could help me. I hope the community have a positive feedback for me. If anyone have another idea, I’m also happy about suggestions how I can solve it.

Thanks in advance for your help.

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