Membership Levels Tutorial or Step-by-step

Following some directions elsewhere here I've got Gravity Forms acting as a front end to a 2nd MySQL database containing our Members (to add new ones). Now I have to get the Paypal side working.

We currently have two levels of Membership, Full and Remote. In our current HTML site, there's a hidden field that contains a 1 o 2 depending on the choice made by the new member and the processing procedure calls the appropriate HTML to contact Paypal and provides the proper product code.

From what I can tell, the Paypal Plugin doesn't do that. Is there a simple, step-by-step example of how I can do this? Or do I have to have a visible field with a Product Code in it (that the user can't touch) that is determined by the member's choice of her membership type and then tell Gravity what to do? (I've read all the docs, but I still don't see where it is I tell GF to tell Paypal WHAT the person is buying!).

Thanks.

Now that I've read some of the documentation <g>, my next question is:
Can I have a hidden product field (or a prevent-entry field) whose value is dependent on a drop-down choice field, e.g., if the choice is "Full Member", then the Product Field has a value of "foo", and if the choice is "Remote" then the Product Field has a value of "bar"?

(And then the Paypal addin is smart enough to know what page to go to, since each product (membership type) has it's own page at Paypal?)

Lawrence

Carl:

Thanks. Can I instead use the "redirect" option to send the user directly to the Paypal page (and not use IPN at present). If so, is it possible to have an "if" statement in the query string?