Dear Concern,
Thanks for sharing your requirements over Freelancer. >> I am expert in Integrating the payment gateways in the websites is also one of my major skill. I have already worked with the PayPal, Amazon Payments, WePay, Eway, Braintree, Stripe.
So >> Let me know about your availability via call/chat for further detailed discussion so that we could be on the same grounds of understanding.
Thanks
Sushil