Paypal Integration Testing...

1. Get details of dummy credit card
2. Checkout button --> Paypal --> Paypal gateway processing --> Back to your website
3. Check for session expiry, session ends.
4. Check what happens if Payment Gateway stops responding.
5. Check for data going to the backend.
6. What happens upon successful transaction -- database, messages, etc.
7. Check receipts are generated and sent to customer email account