CMS custom made

Hello, We are a company looking to build a custom made CMS system based on PHP or CakePHP. The main objective of the system is to help us create multiple websites to our clients in as short process as possible. It has to be able to mange in a few levels in the backend. It has to be easy to change and edit new modules and templates to it. Please bid ONLY if you have high experience in building custom CMS's. With the bid provide links with user+pass to your already made systems.