Set up a secure client area on my wordpress website

I want to be able to have a secure area on my website that people from a client can access and download files from. They should have to register and then login to access the area. Ideally I would like to have a record of who has downloaded what files.
I think this could be done using WP Client but am open to other ways of doing it.
In your proposal, please say how you would intend to do it and how many hours you expect it to take.
Also, so I can quickly rule out people who have not read the brief, please start your answer by giving the name of the capital city of France.