I haven't used it specifically - but your issue with the codepage approach will have to do with that actual API interaction with Paypal. Paypal uses OAuth2 for authentication, which would require that you embed the client ID and secret into a code page which would be a giant red flag in that anyone with access to that page could find it.
You could try and marry a codepage to Pipelines - where Pipelines is operating as your 'server' in this case to handle the actual API interaction with Paypal - but you get iffy results with CORS and the callbacks when trying to work with Pipelines inside of a codepage. Your best bet for simplicity is to use a codepage as the front end within Quickbase and then set up something like an AWS Lambda or Azure instance where you're actually integrating with Paypal, this make the the callbacks much easier to work with.
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Chayce Duncan
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