As regards maintenance, consider it in 3 areas: infrastructure, workstation hardware and software.
Stonar network is fibre-optic and switched right to the desktop with 100/10 switches, mostly Intel, of which more below. Inclusing the Linux servers the whole infrastructure is effectively Maintenance free.
Workstation hardware: The RiscPCs have stood a year in the clasroom since I left and are still running. The desktop PCs of which there are about 20 are hardware-reliable. Laptops are largely pupil-owned and hardware maintenance is an ongoing problem, mostly hard discs and broken screens. All these repairs are subcontracted for liability reasons.
Software: the RiscPCs are locked up solid and are still running as I left them. PC software is a maintenance nightmare with a couple of machines going corrupt every week. When you are trying to deal with Windows in Chinese, it makes an interesting diversion.
As to the switches: the father of one of my A-level ICT students is a director of Intel Europe. I got to know him quite well. The switches were a gift from Intel. Father is totally unfazed by his daughter doing A level under RiscOS. She prefers it by a long way. He actually offered me a set of 'Intel Inside' stickers for the StrongArms. He utters dark warnings about the total collapse of usability of Windows networks as the malware threat grows.