Software that can create one-time sales portal for information to customers

I am selling intellectual property and information from a central website. The issue is that each sale is for unique information/IP, and I have had a hard time finding software that can create a one time sale portal and subsequently deliver that information to the customer. Preferably something that can be integrated with Zapier. Does anyone have any ideas or somewhere they can point me to? I have looked into Ninja Forms but cannot tell if it can do one time payments with intellectual property.