Additional SFTP user/space

It would be great to be able to setup a second SFTP user for an account with their own space in a subdirectory.

I have an ecommerce client that use a distribution/warehouse company for logistics. This distribution company shares a CSV file once per day that we then sync with the site stock levels, to keep them up-to-date. It would be great if we could have a separate and secure SFTP space where the company could upload the CSV, which we could then sync.

Currently I'm using SFTP space elsewhere, but it would be much neater and more manageable if we could do this all together on the same platform.