Oscommerce Customer Upload

I’m looking to either add to my existing site, or setup a new one where customers can upload their files for me to review. I’d also like it if customers could look at the finished product we create and then download it. Preferably the customers would log into there account on our customer portal and have access to such things. This needs to have a web interface so I can access the information from multiple locations. The files need to be stored on our server of course for access reasons. I