You've made a good start.
First, I think you have a lot more research to do, since the original question asks about pricing and where you found your prices.
Second, you need to be a lot more precise about exactly what you're proposing.
x network switches in such-and-such configuration
x feet of cable
x cable ends
x patch cables
x wall plates
x file servers (including operating system)
x wireless access points
Do you want a rack on which to mount everything?
They specify that all network equipment needs to be in the closet, so you should check the length of your longest cable run to make sure it's less than 100 meters.
I also question whether you need two Internet connections. A wireless access point (or wireless router in bridge mode) could connect to a port on your router, so that all traffic is kept separate.