Dear sir,
I have been in this industry for 5 years and such jobs are my daily practice. About my experience , i have 3 year for working and customize Alfresco. I can customize core of Alfresco so that i can help you in this project.
I can assure you that if you work with me once, you will always work with me for these kind of projects. Please contact to me so that we can dicuss in more detail
Have a nice day ,