[Q] [WinServer 2008R2] WebDAV transfer limit and AD auth topic

hi, we want to use WebDAV over IIS to give the users the ability to get on their documents etc over the internet, and I want to ask whether or not there is a way to limit the transfer per user, like 500MB per month

Also we want to do this over AD authentication, but the solution I just read somewhere has the problem it need a kerberos ticket and wont work with foreign PCs over the internet, is there a way to solve that?

Best Regards