Not what I am looking for?

My website is a multi-vendor ecommerce which offers users to subscribe to the listing on weekly or monthly basis. I don’t want to charge the vendor but charge the end user instead. I was also hoping that the end user will be able to buy individual products from the vendor if he wishes instead of subscription. I would like to know if its possible and if not, would like to request a refund as its just the second day after the purchase and the return policy says 30 days.