Is it possible - Reseller FTP - and how?

[ServerQuack]

Since I manage several domains, some of them with aliases and/or subdomains, it would be incredibly helpful to have a Reseller FTP account with which I can gain access across the board if I'm working with files in more than one domain. With Filezilla I can set up accounts to anywhere on my server, but I have no idea how to do that without using my ispCP since I'm not exactly a terminal/ssh guru.
Could someone help me out with that please?
My server is a vServer, not a dedicated root server. Thanks.
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