Mockup design

We are in the design phase of our project. We are looking for a UX /graphic designer who could help us in drafting the idea from our team into a mock-up screen, which would be used by our developers in execute phase.
Approximately 5 screens to be designed (for 3 screen sizes) with high-quality images with a professional outcome.

Job details:
- Our ideation team would come up with ideas of how our product should appear for end users.
- You should be able to interact with them to collect all the ideas and convert them to design.
- All the output should be of high resolution and should have a professional appearance
- Design should be user-friendly solution and should be UX