Some people rightfully consider the addition of a retail payment processing component to a recurring payment processing payment system a great challenge. True, the process involves a lot of major tasks to be solved, such as implementation of card-present EMV solution, new payment processor integrations, addition of retail credit card processing functionality, which enables the payment ecosystem to handle one-time payments smoothly, merchant on-boarding and supporting them throughout their whole life-cycle. However, due to increasing complexity of merchant services market, many businesses need to switch to more universal operations models anyway. So the best option for these businesses is to treat the need to introduce a retail component into a payment ecosystem, initially targeted at subscription billing services, as an opportunity to switch to a more robust and flexible solution.
A detailed transition strategy to be followed by a company, which decides to add a retail component to its existing recurring payment processing ecosystem, is set forth in the respective article on Paylosophy.