Design PSD for Joomla template

I've purchased a group-buying Joomla component and need to change the template. The component developers are willing to customise the template but I need to submit a PSD in order for them to do so. Please see image of the component and default template/theme. The PSD would require changes to the theme in terms of colour, menu positions, and module styles plus additional module positions in the header. I will provide general guidelines for the look and feel, but the designer will be responsible for the final look so creativity and design skills is paramount to this project. Please note that the PSD is required within 72 hours of acceptance of bid.