Design a Website Mockup

I am an entrepreneur starting a new online business and am looking to hire a web designer to design a website mockup/prototype. Site eventually will require taking payments, posting templates similar to Wordpress and allowing customers the ability to create customized websites. This sounds like wordpress but is very different and focused on a very different business than those customers that are creating websites or blogs. Sorry to sound cryptic, but need potential candidates to sign an NDA before I can share more information. Need a highly skilled designer who can potentially program the back end as well. We also are looking for a CTO and this initial position could morph into that role if your talent, intelligence and skill set warrants this. Willing to pay upfront cash and also give equity or some form of both in exchange for the work