I am creating a survey with an optional purchasing component and would like to pass some variables through to a PayPal button at the end of the survey so the user can "Pay Now" and it will automatically populate the amount and recipient (my) info through to PayPal.

Any thoughts or suggestions on this?

Many thanks!

You can place Expression Manager variables in the source code for your button or in the end URL - manual.limesurvey.org/Expression_Manager#Tailoring.2FPiping