if someone needs something like this for free, just contact me…
its simple like that: use blueprints for register, login etc and even directly modify database values by blueprint communicating with a php interface, json and security tokens there is even a account administrating tool based on php, mysql and bootstrap framework
i won’t give much support because of my lack of time but hey because of that its free
you can even setup a monthly fee system within some clicks (if you have paypal)