FTP Server personal folders?

I have an FTP Server on Windows Server 2008 R2 on IIS and can connect to it, but I would like other users (on my computer/domain) to be able to access different folders in virtual directories, but only that folder. Specifically, I would like to be able to give them a link to their virtual directory, and allow them to log in to that folder only, not the root or anyone else's folder. How can I manage the amount of space allowed in the directory? Please be detailed. Thanks.