Programm a Membership Area with a comment system

I search for a Developer how can Programm me a Membership Script. This Means a User can buy on my Wordpress Shop by this payment provider [login to view URL] When he buyed the Membership Script generate a new Access, and a Mail with the Details will be sendet to him. In the Member area i need a Commenting System only, Where he can respond with me what i can do for him. When i Update the Post or him he get a massage and when he respond i got a massage. In the Adminarea i want all Ordert Products. The Oldest order on the Top. Take a look at the Screenshot what is attachd. When i click on one of the orders i can got to the comment system from that Order and can corespond with the buyer. When i have solved the Job i can take in the Massage System a Button. Order solved and the Buyer get a massage and he can came back and download the pdf or so... 3 Days Later the Account would be closed for the buyer. So all Orders get a new access. A Statistik would look be nice but is not critical when it isnt. The Scrip must be runabel on SSL. I search for a long terme programmer. So make a good job and you get more jobs in this side by full time when you want it.