I am using OpenCart right now to allow customers to buy products from my website.

Once they have successfully purchased an item, I would like them to be able to upload a large file (preferrably via FTP) to my server.

Is this possible and how would you recommend I put this together?

I'm guessing I'd have to create a private directory on my server using the orderID.

Or is there a better way of handling this? Should I consider Dropbox?

Many thanks for any help with this :-D