Read Only for all but creator of original file

Question

I need to accomplish the following:
 The goal is for us all to have access to read all the files associated with the audit. Only person posting the file should be able to modify it.
Would this be:
Everyone: Read/Write/Create
Owner: Modify/Delete
As right now they all can read/write/delete any document they would like.

Answer 1

Ah, I see. I'll clarify: you're supposed to set these permissions on the topmost folder
where your users are supposed to create files:
This folder and subfolders:
Everyone - Read and Execute, Create files
Files only:
Everyone - Read and Execute
CREATOR OWNER - Modify
The end result is that users can create files in that folder and all its subfolders - they cannot create folders, but they can read everything. Now, when a user creates a
file in this folder structure, that user and that user only will automatically get Modify on that particular file (the CREATOR OWNER permission is translated to that user account in the ACL).
An example:
Let's say your topmost folder is D:\Data\Users. You apply the above permissions to
this folder. Then, a user with the account name YOURDOMAIN\User1 comes along and creates the file "MyTasks.txt" in this folder. That file will then have the following permissions:
Everyone - Read & Execute
YOURDOMAIN\User1 - Modify
As you can see, there is no need for any special groups. Try it out!