UX Designer User Experience for part of a website screen

I'm looking for an UX designer/ design expert to design a message center for our new homepage. The message center screen is divided into 3 parts (left: contact overview of last messages, middle: chat window, right: booking documentation). The left and middle part are similar to facebooks messaging system. Your offer should include a desktop, tablet and mobile version. For the desktop version, we already have a rough idea of the structure. We expect you to develop multiple design suggestions for each screen, until we are satisfied. Please be aware that we have very high standards and expectations. Background: we are bulding a new platform for childcare services. In the message center, people should be able to talk to each other (particularly parents with babysitters) and also document their agreements, i.e. date and time of the babysitting.