Using Shopify for Services


I understand Shopify is intended primarily for physical products. I have setup my store for drop servicing and would like suggestions on how to run it for this type of 'product'. I can track my services to a degree like a physical product and I don't have shipping, much like a digital product. What else should I bear in mind? I would like to know the best ways to deliver the finished work, as in a way that I can keep my customers informed of their work's progress, and once its done perhaps revisions and then delivery. Thanks!