You are on the right way for sharing the storage and the printers with a NAS connected to the network. Most NAS boxes can share USB printers connected to them. To keep the cost low, i would recommend a 2-bay model and set it up with raid1 (mirroring). The current external drive can be used as the backup drive for the NAS. A bit more difficult will be the sharing of one Outlook Account. I need to think about that. Maybe someone else here has an idea.