I'm not a Subversion pro by any means. But I am using it for my coding projects and using the deployment feature at springloops.com (love it).
I have some log, cache and image folders that I routinely need to make writable on new deployments or new projects. Is there a way to make it so that when deploying or downloading, the folder permissions will already be set to 777?
I don't have a working solution ready. Unfortunately, Subversion properties don't support the setting of permissions. Here Nabble "File Permissions" (external link) is a good discussion and some links about the pro and cons of setting file permissions, eg, via scripting.
svn can't store file (or folder) permissions, so I'm afraid your only option is to write a script to make the task a little less tedious.
When you check out a working copy, by definition you have write access to the whole working copy.