In WordPress, there is one free plugin as s2Member which is used for paid registration membership. In detail about 2Member® (Membership w/ PayPal®). Powerful (free) membership capabilities. Protect members only content. The s2Member Framework (free) integrates w/ PayPal® (very easy), and fully supports recurring billing. s2Member supports custom Pages for registration (including Custom Registration/Profile Fields), account access, and a lot more.
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