The laptop I'm typing this on is connected to my home network via WiFi. And I can access the whole home network, as far as authorisations permit it.
In fact, if I'm in the office, all 1000 employees are connected via WiFi to the office network that includes servers and printers. The servers and printers most likely are connected to the network via Ethernet cables, although for some printers it's quite well possible to do it wireless.
In both cases (home and work), there's only Internet if the modem (that's somewhere in the network) is connected to the ISP (via ADSL, cable, glass fiber or satellite). If that connection is broken, we only have the local (home or office) network. The cloud and external e-mail don't function.
I'd ask your IT staff to set it up to your needs. And when that's done ask them to implement a project management system that doesn't need the cloud, so always works. Then maybe you don't need Internet.
Did you consider to use a wireless 3G or 4G dongle and connect to Internet just like your smartphone does? A subscription of 20 GB of monthly data isn't very expensive. Or is the construction site so far from the civilised world that even smartphones don't have a data connection?
Disclaimer: I am not very techy, so you will have to type slow for me to understand. I am a construction guy, not an IT Wizard. We have a construction project going on and getting internet to the trailers for our construction staff is limited to satellite service only. We want to have a wireless network including a server and printer for the staff of 6. The problem is our ISP is going to charge us $45k to bring a cable into the jobsite. We have are limited to a satellite ISP for the next 2 years. The satellite service is tricky and at time due to weather or whatever, we loose internet service. That is ok at times, but we do a lot of cloud based project management work, so not ideal. We want to have a wireless server and a wireless printer on a network that can maintain operation when the satellite service is down. We still need to print, and we still need to access the server files. Right now the way we are set up, when the satellite service is experiencing an outage, we loose all wifi capabilities. Can someone walk me through what this setup would look like? We have not purchased a wireless server yet, but that is our next purchase and we want that server to back up to our home office server at night. Any assistance would be great.

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