Respecting all below css/design criteria(without going out of scope than the flat design) we need basically
[url removed, login to view]
2-dashboard(also respecting that flat design)
5-two profile versus page( like chat, two people profile pictures will be included one side versus other side.)
All offers will be in respect with that flat ui design using the materials provided (minor/major changes will wellcome within our information)
Just giving you an idea about login take a look at attachment.