Alfresco Setup and Possible Maintenance (open to other software ideas)

I currently work at a small law firm. I am looking for someone to design and setup an open-source SharePoint type solution. From my research, Alfresco seems to be the software most often discussed as the open source alternative. While I say SharePoint and Alfresco, I know they do what I want, but I'm not sure there isn't a better solution out there. So, I am open to suggestion. What follows below is some features I would like. I'm looking for a document management system with check-in/check-out and versioning (I would like at least the previous four versions auto-saved and readily accessible). I would like to be able to have changes emailed to the document creator either in real-time or at the end of the day. I would like the documents to be searchable. I would also like the documents to be organized by libraries with a different library for each client/case. I would also like to have seperate project websites that are accessible by employees inside and outside the office. Those sites should have a calendar specific to the project, a document repository for the project, and a section where people can add tasks and notes. I would also like to have stripped down version of the project sites accessible to clients through a separate login unique to the client. It would be great if documents could be uploaded via email and the site. The vast majority of documents will be Word, Excel, Outlook Messages, and PDF. It would also be great if Wav files (voicemails) could be stored. Will ## Deliverables 1) All deliverables will be considered "work made for hire" under U.S. Copyright law. Employer will receive exclusive and complete copyrights to all work purchased. (No 3rd party components unless all copyright ramifications are explained AND AGREED TO by the employer on the site per the worker's Worker Legal Agreement). ## Platform I don't know. I'm willing to listen to suggestions.