Merging Billing info fields within payment options in magento onepage checkout
I am trying to Merge the billing information fields within Payments options block in magento onepage checkout, something which is similar to the one shown here: https://www.expressvpn.com/order. Basically trying to add the payment options within accordion and merge the appropriate billing info fields to that.
What is the best option to achieve this? Let us know your ideas or if any third party plugins available.