To whom it may concern and I hope it concerns us all because the printer in the art department is out of paper for third time today and those toner cartridges sure aren't cheap!
As far as I know there are only two quota systems specifically with support for gnu+linux. One is Pykota (http://www.pykota.com/) which is Free software but still terrible and Papercut (https://www.papercut.com/) which is proprietary.
I have hoped for a very long time that print user quota support would simply appear as a feature upstream one day in either Cups or Samba. Since it hasn't I am hereby pleading with the developers of Samba to consider implementing it. I am not entirely sure if this is the right codebase for it or if it should be implemented in Cups. I leave this here in the hopes that my small suggestion manages to kick something off.
Correct me if I'm wrong but as far as I know Windows does not have print accounting built in, so this is nothing that Samba can do here either. You might be able to plug in something via CUPS but that's out of our scope.