About people and permissions:
There is no way people can mess with the file system, unless you have set permissions to 777.
That's simply not possible.
The only way it can happen is if you're using a regular un-encrypted FTP connection while working on the site.
Then malicious personage can sniff your username and password easily, and thus gain total access.
The rule is: use SFTP whenever possible.
If your host is not offering SSH access, you can't trust that the source is safe.
It happened to me on Dreamhost once, and after changing all shell passwords and start using SFTP, it hasn't happened since then.
Sorry i should be more specific, what i mean is that i wanted somebody to help me with the appearance of the site and maybe implement new features besides what i already had done.
about the file browsing on my Account, let me give you an scenario:
/home/vince is my accounts home directory,
/home/vince/public_html/xtreme-madden.net is my Yii's app dir
/home/vince/EA-framework is the dir where i keep all the important stuff, like actions to display stats, parse xml, filters, etc ...
If i gave you ftp access to /home/public_html/xtreme-madden.net you could easily write a script similar to the one posted here http://shiflett.org/.../shared-hosting to get the content of the files under /home/EA-framework