FTP account + quota via PHP

[maverick5x]

Hello all.

I was asked to make a web application that allows 3 types of users to upload/download files.
One type of the users which is a prepaid account called golden membership which needs to create a folder in the directory with the username of the registrant and set the quota of that folder to a constant value.

Now my question is how can i create an ftp account and a folder with constant quota, say 1000 MB via PHP?

My client doesnt have any clue about the ftp server nor whether his php has root access or not.

Please advice because this is the first time i am asked to do such a thing.

Thanks in advance.