I am getting close to deployment and this whole time I have been developing a "custom app" for my Shopify store under the basic plan - based off a bunch of fragmented reading, I am realizing that may be a mistake. I now need to figure out the best way to do checkout without using Shopify's webUrl redirect. I have very stringent and specific shipping needs that are being fulfilled by, not only asset-based trucking companies, but massive 3PLs and their respective API integrations. All of this needs to be implemented and displayed in the cart, and then eventually to checkout.
Anyways, in order go to get verified for payment processing in an app, I need to make my app a verified sales channel. To make matters worse, I have quickly found out that private "custom apps" do not qualify for that verification.
Does this mean I need to apply to be a partner, sync up my app with whatever needs to be done there, and apply for payment processing? Or did I maybe overlook something in the Storefront API that can get this done without Shopify Plus?