So I was very intrigued to find a copy of a contract between the County of San Diego, California and Northrop Grumman for "printer resource units," a fancy name for Managed Print Services. You can check it out here. And while you're at it, search the site for "Managed Print Services" and you'll come up with some guidelines for suppliers.
Always interesting to see the government's take on a relatively new service industry.
In fact, Doc has discovered quite few interesting MPS guidelines and requirements by visiting various State websites where most documents (including contracts and bid requests) are public information. Don't say I didn't warn you that with 50 such states, it's easy to spend a lot of time reading the various documents.