Modify joomla component and add payment gateway

We need CCAvenue payment gateway integration to [login to view URL] Joomla component. Along with that we need few other modifications to this template & component also: 1. This has a tier pricing option Example: Lets say current price is INR 100 <Buy Now> On reaching 5, price will increase/decrease to INR 80 On reaching 10, price will increase/decrease to INR 60 In template the buy now button is only with current price, we need buy now button with all the tier pricing options like Lets say current price is INR 100 <Buy Now> On reaching 5, price will increase/decrease to INR 80 <Book at this price> On reaching 10, price will increase/decrease to INR 60 <Book at this price> 2. There should be an option of advance payment. Like if deal is of INR 100 and we want to take only 10% as advance. We should be able to enter 10% at backend and customer should be able to pay only 10% advance and rest at merchant's location or at a later time. 3. Social login which is on registration page should be at top also and should work in a pop up box also. 4. There should be a slider below buy now button which will take value from purchase and show that these many people have bought and these many are minimum required for deal to go through. When it reaches that value it should show some image indicating deal is live. [login to view URL] I will provide the detailed document of the requirement, all the CCAvenue files, image files for the designing part. There will be fixed milestones. If we like the work we will definitely work in future with the freelancer.