The agency you are partnered with must know how to integrate with payment gateways securely and properly. Personal Identifiable Information (PII) should be protected, and PCI best practices should be followed. Here is a list of specific payment gateways that we have experience with Braintree, Stripe, Worldpay, Square, Authorize.net, Elevon, PayPal & Payflow Pro, FirstData, and USAePay.