One little detail to consider. (speaking from experience here): if you want to sell a one time purchase and the customers MAY or MAY NOT have already a specific level (maybe they are already members and maybe not), make sure you use some conditional:
if the customer does not yet have a level, use the code similar to this:
[s2Member-PayPal-Button level=“1” ccaps="whatever you want to call it…
BUT, if you will have some customer that are already into a membership level, you will need to use a a slightly different code, starting like this:
[s2Member-PayPal-Button level="*" ccaps="whatever you want to call it…
In the second case, it will not change the customer’s current level. If you set a level, like in the first example, that one time purchase might cancel the recurring payment. I am not 100% sure with Stripe, but i have had that experience many times since i have ONE membership, and several Buy now products. It is quite an inconvenience when the single purchase cancels the subscription and the customer receives a notification that YOU cancelled it!
The solution: wrap the button/form within a conditional to show one button to those without a current level, and another button to those with a current level.