Write access for author but no access to other files

I am pulling my hair out and wasting lots of time on this one... I'm using
NTFS permissions and have a shared folder that will have various documents
inside but not necessarily and subfolders. While I need to grant some users
full control of all the data within this share, I also need to limit some
users to ONLY adding and editing their own documents. It's ok that they can
see the other files, but cannot have read/write access to them. I've toyed
with the Creator/Owner permissions with no luck and it appears that part of
the problem there is that under "special permissions", it only allows the
permissions for that group to be applied to subfolders and files, not to the
current folder... Any ideas are greatly appreciated!!!