Customizing Vode.. help

I'm creating a site where customers need to purchase credits to view content(pics/videos). The customer can buy credits so that they have some in there account or they can purchase them when there ready to buy content. When they buy content they can choose the amount of days they want to view it for. For instance I want to buy a video which is worth 30 credits and I want to view it for 1 day which is worth 10 credits, so that takes 40 credits from there account. After the credits are taken the content will show up in there account. There will also be weekly group cam shows  and one on one shows. Customers will need a certain amount of credits to view live shows. I know this type of programming is possible, vodes is the closest extension I found for what I need for my site. I know nothing about programming so I wouldn't know the right coding to add to vodes. Another thing is that some of my content is for 18+ and paypal doesn't support adult content. What kind of coding do I need to implement theses features(without using paypal)? How much would it cost to implement these features to vodes and or How much would it cost to create a extension from scratch if I can't use paypal/vodes?