How to build a website that allows clients to upload content and then allow certain users to download that content

Ok, I ll try to be as concise as possible.

What I want:

1. I want to build a website that will allow clients to sign up for a small fee and allow them to upload content to their UNIQUE USER FOLDER.
2. General users will then be able to sign up for free and request to download specific files from various clients (not just one). Administrators will manage all user requests to download clients files. Once approval is given by administrators, an email will be sent to the user stating that they may now login to download the files.
3. User logs in and in their homepage, the files that they have been approved to download are now visible as a download or play in browser option.
4. User downloads file, modifies it, then upload the modified file back to the respective clients folder.

Problems I am having:

• Would a CMS like drupal, joomla, etc work best for this type of website, or would it have to be a custom all the way? Most CMS's don't allow users to have private folders, etc. Which CMS or approach would you suggest? And if they do allow user folders, then how would I get around to having the user access only those specific CLIENT'S folder in order to download their files?
• I want everything to be automated, except for administering which fi开发者_如何学Pythonles get assigned to what user.

I have considered Drupal for a while for something like this, and have even tried testing it out, but it seems that there would have to be TONS and TONS of customizations that I question if it would be easier to just start from scratch. But I also don't want to re-invent the wheel, you know? Also, whatever system is chosen MUST be able to handle heavy traffic volume, as there would be users and clients logged in constantly, uploading and downloading files at all times.

Any suggestions or input??? Thanks.

drupal: To realise a document management which does all you describe in drupal needs quite some work and knowhow, I admit you're right.

If you still need advise and/or help with drupal, write back.

Since a few month this is mostly my business and i guess i can help along.

I possibility for you to consider is wordpress.

Although it is a blogging platform has become en my opinion a CMS by know.

I do do go for it you could use: Codex

Another possibility would be with Joomla! with advanced module management

Read this discussion:

http://forum.joomla.org/viewtopic.php?f=428&t=557134

There are more plugins available that could suit you better.

Good luck please ask for any clarifications if needed!

EDIT:

For drupal you might find useful something like this

And I forget, unless you are quite an experienced developer I would go on developing a CMS platform myself and it is not necessary to build a custom one I you manage one or two good workarounds.

EDIT:

Sorry for so much edits, for the user upload you should search for plugins for this purpose for all of the mentioned CMS BUT be ware of vulnerabilities, be sure to ask around before!!