Special FTP setup

[heymrdj]

Here's my situation. My host runs on a shared IP so i can't use anonymous FTP. How would I set up an FTP so users can't go off deleting my files? Or better yet how I would lock my chmod from other users changing it. I have these folders of files. I have to create a custom FTP account that allows connection to just the FTP folder I made. But when I make this that gives them full rights to the folder. So to counteract that I chmoded the folder to 500 so it could only be read and executed but no one could delete anything. but then after error proofing it I found out that with just about any free FTP client people could change the chmod then delete it to be hateful. (there has been alot of that happening all of a sudden). So basically is there any way I could make those extra FTP accounts I created of a lower status than my main ftp account that comes with my hosting. That way I could make that group into others and chmod them from being able to delete. Of course I don't have to go this route. if anyone has any ideas on how to get by this plz let me know. Thank You

[heymrdj]

Let me rephrase the question just in case my last post was a little confusing. Is there any way to change FTP permissions so that people can download and upload without being able to delete files. Cause I tried chmod but of course anyone using a FTP client can change the chmod and then be able to wreak all the havok they wanted.