download file - for existing customer

Hi,

We plan to sell services, what we need is that a customer can go back in his account and download a report file (a month later).
This report file should not be available for other customer and there is no extra cost for that report.

Any clue how to achieve this or is any existing module can do the job?

Thanks

Lenamtl

I' m wondering is there any development on this feature since my post?