Multifunction Laser Printer Storage

I work for Florida Fish and Wildlife and I have been asked to find out about storage within the multifunction laser printers at dell.  Recently, there has been talk about coppiers with Hard Drives that store the data temperarly (until overwritten) and they have become a security risk because printers, scanners, and coppiers often leave the agencies without anything being prepped (hard drive being wiped). Our agency primarly buys its printers from dell and I am curious if anybody knows if and how data is stored on the multifuction printers when people are scanning or copying, if there are internal hard drives or flash memory that the data stores to, and if it is flash memory and it does store data what would be the best way of clearning the data (I believe a reset would sufficiently wipe anything stored within flash memory)?