The client's requirements are pretty relaxed. Looking at pricing for shopify and stripe, they take the same transaction fees and shopify just adds a 29$/month charge, since the buisness is small enough I assume they would buy the basic plan.

The client is likely fine with either option, what I'm most interested in is getting a working result without getting stuck, while still learning as much as I can from this. I've had a lot of trouble finding a job so I am trying some solo projects to try to get my feet wet in the industry.