SVN
SVN is currently hosted on Backus, so make sure you are on that server.
To create a new repo, run the following command:
svnadmin create /var/lib/svn/reponame
When this is done, make sure /var/lib/svn/reponame and it's contents are owned by www-data.
To allow users to read/write to the repo add the appropriate information to /etc/svn/svn.authz:
[reponame:/] joeblogs = rw #joeblogs can read and write to the repo otheruser = r #otheruser can read the repo * = r #everyone can read the repo