The numbers we look after here are.
Circa 320 desktops and laptops
Several dozen teaching rooms with extensive AV
Lots of voip and older digital phones
Dozen or so video conference rooms
Specialist teaching technology.
Vast amounts of Wireless APs
Mostly windows 7 and 10 with less than 5 macs
ohh and about 10 or so servers.
All that on 2 and a half folk, we do the AV, pc and decent amount of lvl3 support as well - phones, networking... its all done.
Point is if you have good procedures written for everything and good backup (ie people to call when things go banana shaped) you can do a lot with not a lot of bodies. Just need to get the right folk.