The idea you imagined is quite complex and requires many more engagements, people, resources... It is not enough to just install WP+specific themes and announce a new project, even with demo content posted by the theme developer.

Here you have already received enough feedback for some important things, such as scam prevention and control of user interaction, so based on that alone, you can understand that your idea is not a one-man show. Consequently, you would have to first do a little more detailed analysis of your idea and see your capacities, and only then get involved in the whole thing