You would put this out to bid and then look over their proposals.
The killer item to me were those phones. WiFi isn't reliable enough to host all you noted so they should push back on that aspect.
If I read your post a second time you are asking why it goes down. That would be WiFi links. WiFi is an open standard that can be easily brought down with well, the internet is full of the reasons why so I no longer list them. WHAT you need is a non-WiFi link that is proprietary and not subject to such interference. These are sold by networking companies that include site inspection and more.
I'm with a small business that works in e-commerce. My ISP is Metronet. When they added their services they did not provide a modem. I guess our small belkin home router acts as the modem as it has a static IP and is the hub for all network activity. We have two separate buildings just a hundred feet apart. In the primary building we have 4 computers hard wired, and then a wireless printer an ipad and 2-4 phones connected at once. we then have a hard wire connection to an access point (very beefy machine that should cause no issues) located on the exterior wall on the peak of the roof, of the main building. This access point then provides network access over to the adjacent building I described. The connecting point here is network extender (this is another home network piece of equipment). This extender has 2 hard wires going to computers as well as wireless access for an ipad and 2-4 phones as well. The way we have it setup is clearly not working as we are constantly having trouble with the network going down in one building and sometimes both. What I would like to find out is: What is the causing it to go down.
And of course how do I fix it (whether it be redoing what we have or buying new equipment.)
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