Add PayPal integration into OpenQuote. Include all major forms of PayPal (Standard, Pro) and allow PayPal Subscription (recurring payments) to be supported.

PayPal should be able to turned on and configured inside the product configuration, and setup may be different between products, ie a life product may only offer subscription payments, whereas holiday insurance from the same insurer/broker may only allow a one off payment.

This Jira has two sub-jiras, one for analysis, and one for implementation.