a mockup website

I'm looking for an experienced designer who can create a website mockup for an e-commerce site built on Shopify. I have a general idea of what I would like included in the mockup, however I'm also open to suggestions from the designer. The goal of the mockup is to act as a prototype for the entire website, and will ultimately be used as the foundation for the full site. The designer should be prepared to make adjustments, as needed, to ensure the mockup properly reflects the desired design. Once complete, the client should be able to easily use the mockup to move forward with the project.