Integrating Paypal (Direct) to website & Social nw

I have a online simple e-comm template This is a template i purchased online and I would like to customize it. The template works fine and can checkout using Paypal. 1) I would like to integrate a Direct Payment method using Paypal's gateway in the site (I can get SSL) [meaning the people would have credit card authorization in my site itself without going to Paypals site.] 2) Add quantity option in the first page itself (now it is not functional but you can see the html part in the index page). 3) Add Open ID technique to login and checkout. Store all info of the user expect their CVV number which would be required to login again. So once the user enters the info first time, they will be prompted to integrate one of their Social nw logins with this account so next time they just have to login with this same Social nw credentials.