UI/UX Expert Wanted To Improve Existing Website

I am looking for a UI/UX developer with experience of creating Mockups and wireframes for websites, to create for an existing web application. These mockups will be for mobile and desktop views.

The UX expert will have knowledge of Job post workflows (similar to pph and fiverr) as that is one of the main features to be builtin addition to iTunes store workflow(as digital music is sold there also).

A vital part of this whole process is to improve on what we have at the moment so you will also be going through competitor websites in order to improve on certain user journeys/experience on the existing application.
The mockups and wireframes will have to be clickable as user journey flow including happy and unhappy paths.

The ideal person will be someone who can work with our team to gather the business requirements and turn them into the relevant mockups and wireframes

Please only apply if you are able to satisfy the criteria requested above and also provide relevant portfolio.