Email List Exchange Platform

I need someone to design a fully-functioning platform for email list exchanging for marketeers. People who have an email list database can exchange with people from the same niche. For example: I have 5000 emails in the weight-loss niche, and I exchange those emails with someone that also has around 5000 emails in that same niche, so that we both have 10,000 emails after that. Then I can go to another person from the platform and exchange again to have more emails. Needed functionality: - There needs to be an email validator that will check emails if they are valid - There needs to be a system that checks emails from both sides for duplicates, so that people don't receive the same emails that they give - There needs to be a feedback rating system that serves to show good vendors - It should be designed like a marketplace: - For Example: John Doe had 4,536 emails in the "Online Marketing Niche", would you like to exchange with him?